"Science, Faculty of"@en . "Zoology, Department of"@en . "DSpace"@en . "UBCV"@en . "Filmer, Norman John"@en . "2011-09-26T23:34:01Z"@en . "1964"@en . "Master of Science - MSc"@en . "University of British Columbia"@en . "This thesis is an amalgamation of and a contribution to the knowledge of the Ephemeroptera of British Columbia, an order which has been largely neglected in Canada, and particularly in this province. The three families Heptageniidae, Ephemeridae, and Baetidae are replaced by the five superfamilies Heptagenioidea, Leptophlebioidea, Caenoidea, Ephemeroidea, and Prosopistomatoidea proposed by Edmunds and Traver (1954). 146 species in 23 genera have been recorded in British Columbia. Of these, 62 as yet unidentified species are designated by number. A checklist of all recorded species, and keys and descriptions of taxonomically important criteria of the species and higher ranks are included herein. A preliminary investigation of the ecology of the nymphs collected by the author in the Alouette River and by Dr. G.G.E. Scudder in the lakes of the Chilcotin, Cariboo, and Nicola Valley regions revealed no \"preference\" of the nymphs for the middle or edges of the river or for particle size of the substrate. An accurate determination of the latter, however, is not obtainable with the type of collecting equipment employed during this study. Some \"preference\" was shown by a number of species for specific rates of current flow. No correlation between the species of nymphs and the pH or the salinity of the environment was determined. Suggestions are put forward for the extension of our knowledge of the taxonomy, ecology, and biology of the Ephemeroptera."@en . "https://circle.library.ubc.ca/rest/handle/2429/37620?expand=metadata"@en . "A C O N T R I B U T I O N T O T H E E P H E f f l E R O P T E R A O F B R I T I S H C O L U M B I A by NORMAN JOHN FILMER 8 . 5 c , U n i v e r s i t y o f B r i t i s h C o l u m b i a , 1958 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF Mast e r o f S c i e n c e i n t he Department of Zoology 'die a c c e p t t h i s t h e s i s as c o n f o r m i n g t o the r e q u i r e d s t a n d a r d THE UNIVERSITY OF BRITISH COLUMBIA October, 1964. In p r e s e n t i n g t h i s t h e s i s i n p a r t i a l f u l f i l m e n t of the r e q u i r e m e n t s f o r an advanced degree a t the U n i v e r s i t y of B r i t i s h C o l u m b i a , I a g r e e . t h a t the L i b r a r y s h a l l make i t f r e e l y a v a i l a b l e f o r r e f e r e n c e and s t u d y . I f u r t h e r agree t h a t p e r m i s s i o n f o r e x t e n s i v e c o p y i n g of t h i s t h e s i s f o r s c h o l a r l y purposes may be g r a n t e d by the Head of my Department or by h i s r e p r e s e n t a t i v e . I t i s u n d e r s t o o d t h a t c o p y i n g or p u b l i c a t i o n of t h i s t h e s i s f o r f i n a n c i a l g a i n . s h a l l not bs a l l o w e d w i t h o u t my w r i t t e n p e r m i s s i o n . A B S T R A C T T h i s t h e s i s i s an amalgamation o f and a c o n t r i b u t i o n t o the knowledge o f the Ephemeroptera o f B r i t i s h C o l u m b i a , an o r d e r which has been l a r g e l y n e g l e c t e d i n Canada, and p a r t i c u l a r l y i n t h i s p r o v i n c e . The t h r e e f a m i l i e s H e p t a g e n i i d a e , Ephemeridae, and B a e t i d a e a r e r e p l a c e d by the f i v e s u p e r f a m i l i e s H e p t a g e n i o i d e a , L e p t o p h l e b i o i d e a , C a e n o i d e a , Ephemeroidea, and P r o s o p i s t o m a t o i d e a p roposed by Edmunds and T r a v e r ( 1 9 5 4 ) . 146 s p e c i e s i n 23 genera have been r e c o r d e d i n B r i t i s h C o l u m b i a . Of t h e s e , 62 as y e t u n i d e n t i f i e d s p e c i e s a r e d e s i g n a t e d by number. A c h e c k l i s t of a l l r e c o r d e d s p e c i e s , and keys and d e s c r i p t i o n s o f t a x o n o m i c a l l y . i m p o r t a n t c r i t e r i a o f t h e s p e c i e s and h i g h e r r a n k s a r e i n c l u d e d h e r e i n . A p r e l i m i n a r y i n v e s t i g a t i o n o f the e c o l o g y of the nymphs c o l l e c t e d by the a u t h o r i n the A l o u e t t e R i v e r and by Dr. G.G.E. Scudder i n the l a k e s o f the C h i l c o t i n , C a r i b o o , and N i c o l a V a l l e y r e g i o n s r e v e a l e d no \" p r e f e r e n c e \" o f the nymphs f o r the m i d d l e o r edges o f the r i v e r o r f o r p a r t i c l e s i z e o f the s u b s t r a t e . An a c c u r a t e d e t e r m i n a t i o n o f the l a t t e r , however, i s not o b t a i n a b l e w i t h the type o f c o l l e c t i n g equipment employed d u r i n g t h i s s t u d y . Some \" p r e f e r e n c e \" was shown by a number of s p s c i e s f o r s p e c i f i c r a t e s of c u r r e n t f l o w . No c o r r e l a t i o n between the s p e c i e s o f nymphs and the pH o r the s a l i n i t y o f the environment was d e t e r m i n e d . S u g g e s t i o n s a r e put f o r w a r d f o r the e x t e n s i o n o f our knowledge of t h e taxonomy, e c o l o g y , and b i o l o g y o f the Ephemeroptera. - i v -I w i s h t o e x p r e s s my i n d e b t e d n e s s to Dr. K. Graham, Dr. R.A. R i n g , and Dr. G.G.E. Scudder of the Department o f Zoology of the U n i v e r s i t y o f B r i t i s h Columbia f o r t h e i r v e r y h e l p f u l c r i t i c i s m s and encouragement d u r i n g the p r e p a r a t i o n of t h i s t h e s i s . I am e s p e c i a l l y g r a t e f u l t o Dr. Scudder, who i s r e s p o n s i b l e f o r my i n t e r e s t i n the Ephemeroptera, f o r s u p e r -v i s i n g my work, f o r making a v a i l a b l e t o me h i s own c o l l e c t i o n and t h a t o f t h e U n i v e r s i t y , and f o r p r o v i d i n g me w i t h i n s p i r a t i o n . I would a l s o l i k e to s i n c e r e l y thank Dr. G.F. Edmunds and Dr. R.K. A l l e n of the U n i v e r s i t y of Utah f o r i d e n t i f y i n g the nymphs of my own c o l l e c t i o n , and Dr. T.G. N o r t h c o t e of the U n i v e r s i t y o f B r i t i s h Columbia f o r making a v a i l a b l e t o me the c o l l e c t i n g equipment used d u r i n g t h i s s t u d y . I would l i k e to e x p r e s s a s p e c i a l t h anks to fflr. G.3. Spencer of t h i s u n i v e r s i t y f o r p r o v i d i n g me w i t h the thorough taxonomic f o u n d a t i o n n e c e s s a r y t o the accomplishment of t h i s t h e s i s . - i t -T A B L E O F C O N T E N T S P a, \u00C2\u00A3 a I . Acknowledgements i v . I I . I n t r o d u c t i o n ' 1 I I I . m a t e r i a l s and Methods 4 IV. C h e c k l i s t o f B r i t i s h Columbia Ephemeroptera 12 V. A s y s t e m a t i c a c c o u n t of the a d u l t s and nymphs of the B r i t i s h C o l umbia Ephemeroptera 20 V I . D i s c u s s i o n and C o n c l u s i o n s - 211 V I I . Summary 216 V I I I . L i t e r a t u r e C i t e d 218 - i i i -L I_ 5 T \u00C2\u00A3 \u00C2\u00A3 J. L L. U S T R A. T I 0 N S \u00C2\u00A3 a \u00C2\u00A3 \u00C2\u00A3 PL.ATL\ I 222 F i g . 1. A diagram o f the main t o p o g r a p h i c f e a t u r e s of a m a y f l y wing (based on a f o r e wing o f < j r o n o p s i s permagnus). F i g . 2. R e p r e s e n t a t i v e mouthparts of the m a y f l y nymph. PLATE I I F i g . 3. fflale . g e n i t a l i a of some Heptagenine and B a e t i d nymphs. 223 The o r d e r Ephemeroptera r e p r e s e n t s a major taxonomic group of i n s e c t s of c o n s i d e r a b l e e c o l o g i c a l i n t e r e s t and economic i m p o r t a n c e . T h e i r taxonomy has been f o r the most p a r t n e g l e c t e d i n Canada. T h i s n e g l e c t r e p r e s e n t s an impediment to any sound b i o l o g i c a l work i n which i t i s n e c e s s a r y t o d e f i n e the m a t e r i a l and d i f f e r e n t i a t e between l i f e f o r m s . Many w o r k e r s i n the U n i t e d S t a t e s have p u b l i s h e d taxonomic r e v i e w s of the Ephemeroptera of t h e i r p a r t i c u l a r r e g i o n s , a l t h o u g h t h e r e has been a s c a n t amount p u b l i s h e d i n the p a s t t e n y e a r s . A.E. E a t o n (1883-1888, 1901) p i o n e e r e d t h e study on t h i s c o n t i n e n t . P r o b a b l y the most p r o l i f i c c o n t r i b u t o r t o the taxonomy of t h i s o r d e r was 3, McDunnough, who p u b l i s h e d a g r e a t many papers on the N o r t h America s p e c i e s over a twenty year p e r i o d e n d i n g i n 1943. Some of the more i m p o r t a n t workers i n t h i s f i e l d a r e UJ.Ui. U p h o l t (1936, 1937) and U.K. Mayo (1951, 1952) on the West C o a s t ; UJ.C. Day (1954, 1955) i n C a l i f o r n i a ; H.T. S p i e t h (1941, 1947), N o r t h America i n g e n e r a l ; L. Berner (1956) i n F l o r i d a ; and B.D. Burks (1946, 1949, 1953) i n I l l i n o i s . The o n l y comprehensive s t u d y of t h i s o r d e r i n N o r t h America i s the e x c e l l e n t volume, The B i o l o g y of M a y f l i e s , by 3.G.' Needham,' 3.R. T r a v e r , and Y i n - C h i Hsu i n 1935. The most i m p o r t a n t workers a t p r e s e n t are G.F. Edmunds, 3.R. T r a v e r , and R.K..-'Allen, Edmunds and T r a v e r ( 1 9 5 4 ) , Edmunds (1962) have r e v i s e d t h e taxonomy of the o r d e r , r e p l a c i n g the o r i g i n a l t h r e e f a m i l i e s w i t h f i v e s u p e r f a m i l i e s . Edmunds and T r a v e r (1959, 1963) are a t p r e s e n t r e v i s i n g the Genus E p h e m e r e l l a . Very l i t t l e has been done on the Canadian Ephemeroptera. F.P. Ide (1954) has -2-done a l a r g e amount of mark on the O n t a r i o Ephemeropterans. C o n t r i -b u t i o n s i n t h a t p r o v i n c e have a l s o been made by lil.ffl. S p r u l e s ( 1 9 4 7 ) , The o r d e r has not been i n v e s t i g a t e d a t a l l i n the r e s t o f the c o u n t r y , i n c l u d i n g B r i t i s h C o l u m b i a . The Ephemeroptera i s a p a r t i c u l a r l y s a t i s f a c t o r y group w i t h which t o work, f o r a l t h o u g h the members are f r a g i l e , they e x h i b i t e x c e l l e n t m o r p h o l o g i c a l c r i t e r i a . These i n c l u d e body form, wing v e n a t i o n , the p r o p o r t i o n s o f the l e g segments, g e n i t a l i a and c o l o u r p a t t e r n i n the a d u l t s ; and body form, mouth p a r t s , g i l l s and c o l o u r p a t t e r n i n t h e nymphs. There i s , however, a d i f f i c u l t y , p a r t i c u l a r l y i n the c o n s t r u c t i o n o f k e y s , i n t h a t the a d u l t s o f the s e i n s e c t s e x h i b i t c o n s i d e r a b l e s e x u a l dimorphism, which i s m a n i f e s t e s p e c i a l l y i n the c o l o u r , l e g segment p r o p o r t i o n s , and wing v e n a t i o n . An a t t e m p t has been made i n the f o l l o w i n g keys t o m i n i m i z e t h i s d i f f i c u l t y wherever p o s s i b l e by employing c o u p l e t s which do not c o n s i d e r c o l o u r , l e g segment p r o p o r t i o n s , and wing v e n a t i o n i n t h o s e groups d i s p l a y i n g a marked s e x u a l dimorphism i n t h e s e c r i t e r i a . The use of g e n i t a l i a as a taxonomic f e a t u r e i s k e p t to a minimum because t h e i r use p r e s e n t s t e c h n i c a l d i f f i c u l t i e s and i n c o n v e n i e n c e to t h o s e who may w i s h t o employ the key. However i t i s i m p o s s i b l e t o e l i m i n a t e t h e s e c h a r a c t e r i s t i c s e n t i r e l y . The c o n s i d e r a b l e v a r i a t i o n i n body form of the nymphs among the v a r i o u s s p e c i e s a f f o r d s an e x c e l l e n t o p p o r t u n i t y to s t u d y the r e l a t i o n s h i p between t h e i r morphology and e c o l o g y . - 3 -B r i t i s h Columbia i s a p a r t i c u l a r l y c o n v e n i e n t a r e a f o r the s t u d y of the Ephemeroptera, due t o the d i v e r s i t y o f the e c o l o g i c a l z o n e s , the abundance and a c c e s s i b i l i t y o f l a k e s and r i v e r s , and the number of a v a i l a b l e specimens i n the c o l l e c t i o n o f the U n i v e r s i t y o f B r i t i s h C o l u m b i a . The p r e s e n t s t u d y was t h e r e f o r e u n d e r t a k e n to c l a r i f y the taxonomy o f t h e Ephemeroptera of B r i t i s h C olumbia c o n s i s t e n t w i t h the newer i d e a s o f taxonomy o f t h i s group. I n c l u d e d are a c h e c k l i s t o f a l l s p e c i e s r e c o r d e d from t h e p r o v i n c e , keys o f a d u l t s and nymphs, d e s c r i p t i o n s of t h e c h a r a c t e r i s t i c s o f taxonomic i m p o r t a n c e , and where p o s s i b l e , some ac c o u n t of t h e i r e c o l o g y . For a d i s c u s s i o n of t h e v e r y i n t e r e s t i n g l i f e h i s t o r y o f the m a y f l i e s , and f o r an e v a l u a t i o n o f t h e i r economic i m p o r t a n c e , e s p e c i a l l y as a s o u r c e o f f i s h f o o d , I r e f e r the r e a d e r t o the v e r y e x c e l l e n t a c c o u n t s of Needham, T r a v e r , and Hsu ( 1 9 3 5 ) . -4~ M A T E R I A L S A N D M E T H O D S The m a t e r i a l examined d u r i n g t h i s s t u d y came from t h r e e s o u r c e s , my own c o l l e c t i o n s on the A l o u e t t e R i v e r near Haney, B r i t i s h C o l u m b i a , the c o l l e c t i o n s of Dr. G.G.E. Scudder from l a k e s i n the C h i l c o t i n , C a r i b o o , and N i c o l a V a l l e y r e g i o n s , and the s p i r i t c o l l e c t i o n of nymphs and the c o l l e c t i o n of p i n n e d a d u l t s o f the U n i v e r s i t y of B r i t i s h C o l u m b i a . \u00E2\u0080\u00A2 A l l specimens from t h e s e t h r e e s o u r c e s were examined and i d e n t i f i e d o r d e s c r i b e d . The system o f c l a s s i f i c a t i o n employed i n t h i s paper i s t h a t proposed by G.F. Edmunds and 3.R. T r a v e r , i n which the t h r e e f a m i l i e s H e p t a g e n i i d a e , Ephemeridae, and B a e t i d a e are r e p l a c e d by the s u p e r f a m i l i e s H e p t a g e n i o i d e a , L e p t o p h l e b i o i d e a , C a e n o i d e a , Ephemeroidea, and P r o s o p i s t o m a t o i d e a . A l l e x c e p t the l a s t a re r e p r e s e n t e d i n B r i t i s h C o l u m b i a . An a t t e m p t was made t o i n v e s t i g a t e the e c o l o g i c a l r e l a t i o n -s h i p s of the nymphs c o l l e c t e d i n the A l o u e t t e R i v e r . T h i s r i v e r was chosen because of i t s p r o x i m i t y t o Vancouver, i t s a c c e s s i b i l i t y , and the v a r i o u s t y p e s of h a b i t a t s i t a f f o r d s from i t s headwaters to i t s mouth. The r i v e r i s d i v i d e d i n t o two arms, the N o r t h and the S o u t h . The former d r a i n s M a r i a n Lake, r u n n i n g f o r a p p r o x i m a t e l y t e n m i l e s to meet the South arm, which runs a t e n m i l e c o u r s e from A l o u e t t e Lake. The r i v e r , then f l o w s a p p r o x i m a t e l y two m i l e s t o empty i n t o the P i t t R i v e r . The w i d t h of the r i v e r v a r i e s from twenty f e e t a t t h e headwaters to s e v e n t y - f i v e f e e t near the mouth. The r a t e of f l o w and c h a r a c t e r of the s t r e a m v a r i e s , b e i n g g e n e r a l l y f a s t e r and more t u r b u l e n t near the o r i g i n s and slow and p l a c i d near - 5 -the mouth. There a re a l s o s t a g n a n t and q u i e t ponds and bac k w a t e r s a l o n g the l e n g t h of t h e r i v e r . The c h a r a c t e r o f the stream bed v a r i e s from the r o c k s and b o u l d e r s o f the headwaters t o mud and s i l t near the mouth. Areas o f g r a v e l and sand a re a l s o p l e n t i f u l and always i n c l o s e a s s o c i -a t i o n w i t h l a r g e r r o c k s . V e g e t a t i o n i n the r i v e r i s s p a r s e , and c o n s i s t s f o r the most p a r t o f v a r i o u s t y p e s o f mosses. At the b e g i n n i n g o f fflay 1959 the r i v e r was mapped and the c h a r a c t e r o f f l o w and the stream bed a t a l l a c c e s s i b l e p o i n t s was n o t e d . Twenty-two of t h e s e p o i n t s were c h o s e n , c a r e b e i n g t a k e n to u t i l i z e as many d i f f e r e n t t y p e s o f h a b i t a t s as p o s s i b l e . These were d i v i d e d i n t o t h r e e groups o f s t a t i o n s , and each week c o l l e c t -i o n s were made from one group, so t h a t each s t a t i o n was v i s i t e d e v e r y t h r e e weeks. D u r i n g the w i n t e r , from September to May, each s t a t i o n was v i s i t e d e v e r y s i x weeks. At each s t a t i o n c o l l e c t i o n s were made from one t o f o u r h a b i t a t s , u s u a l l y t he m i d d l e arid edge o f the r i v e r , and any ba c k w a t e r s or ponds. The edge of t h e r i v e r was c o n s i d e r e d to be t h a t p o r t i o n a c c e s s i b l e by a d i p n e t m a n i p u l a t e d from the bank. The components of the stream bed were d i v i d e d f o r d e s c r i p t i v e p u r p o s e s i n t o e i g h t t y p e s , based on ap p r o x i m a t e p a r t i c l e s i z e -mud, sand, f i n e g r a v e l ( p a r t i c l e s up to 5mm. i n s i z e ) , c o a r s e g r a v e l ( p a r t i c l e s from 6mm. to 2cm. i n s i z e ) , s m a l l r o c k s (from 2cm. to 12cm. i n s i z e ) , l a r g e r o c k s (any r o c k l a r g e r t h a n 12cm. but r e m o v a b l e ) , b o u l d e r s (any immovable r o c k ) , and bedr o c k . -6-The s w i f t n e s s of t h e c u r r e n t i n most l o c a t i o n s p r o h i b i t e d the measurement of c u r r e n t speed w i t h a c u r r e n t meter. T h e r e f o r e i n l i e u o f more a c c u r a t e measurement of r a t e of f l o w , the f o l l o w i n g d e s c r i p t i v e p h r a s e s are used: q u i e t or s t i l l , s low ( a p e r c e p t i b l e c u r r e n t but w i t h o u t r i p p l e s ) , slow r i p p l e s , f a s t r i p p l e s , and r a p i d ( w i t h t u r b u l e n t , w h i t e w a t e r ) . (Iflost c o l l e c t i n g was done w i t h an o r d i n a r y d i p n e t , a l t h o u g h i n some c a s e s a S u r b e r Sampler (Needham and U s i n g e r , 1956) was used. In deep w a t e r near the mouth o f t h e r i v e r , an Ekman dredge was l o w e r e d from v a r i o u s b r i d g e s . The m a t e r i a l c o l l e c t e d was brought i n t o the l a b o r a t o r y , c o u n t e d , i d e n t i f i e d t o f a m i l y o r o r d e r , and p r e s e r v e d i n a l c o h o l f o r more a c c u r a t e i d e n t i f i c a t i o n a t a l a t e r d a t e . A b r i e f d i s c u s s i o n a t t h i s p o i n t o f the taxonomic f e a t u r e s of the Ephemeroptera might b e n e f i t r e a d e r s u n f a m i l i a r w i t h the o r d e r . A l t h o u g h t h e r e i s c o n s i d e r a b l e v a r i a t i o n i n morphology among th e v a r i o u s s p e c i e s and among h i g h e r r a n k s , the m o r p h o l o g i c a l d e t a i l s a r e r e m a r k a b l y c o n s t a n t w i t h i n a s p e c i e s . The body form o f t h e a d u l t v a r i e s from l o n g and s l e n d e r to s h o r t and t h i c k . The antennae a r e s h o r t and s e t a c i o u s . The compound eyes are u s u a l l y l a r g e r i n the male than i n the f e m a l e , and may be a p p r o x i m a t e d a p i c a l l y i n the f o r m e r . In some groups the d o r s a l p o r t i o n s a r e l i g h t e r i n c o l o u r t h a n the v e n t r a l p o r t i o n s , as i n the genera S i p h l o n u r u s and H e p t a q e n i a . The eyes i n the genera B l a s t u r u s and E p h s m e r e l l a are d i v i d e d i n t o a l a r g e r , l i g h t e r upper p o r t i o n and a s m a l l e r , d a r k e r l o w e r p o r t i o n by a t r a n s v e r s e g r o o v e , and i n a l l the B a e t i n a e the eyes a r e c o m p l e t e l y d i v i d e d , the upper p o r t i o n b e i n g t u r b i n a t e . A l l s p e c i e s have t h r e e o c e l l i , a r r a n g e d t o form a t r i a n g l e , t he d i s t a n c e s between them v a r y i n g . The wings are not f r a g i l e , as b e f i t s an i n s e c t t h a t spends the major p a r t o f i t s a d u l t l i f e i n the a i r . They are s t r o n g l y a t t a c h e d t o a w e l l - d e v e l o p e d t h o r a x which c o n t a i n s the p o w e r f u l muscles o f f l i g h t . They are u s u a l l y h y a l i n e , b u t may be t i n t e d brown or amber, or s u f f u s e d w i t h b r o w n i s h or b l a c k i s h c l o u d s . The v e n a t i o n i s p a l e o r d a r k . The f o r e w i n g s a r e l a r g e , f a n - s h a p e d , and f l u t e d . They can be d i v i d e d i n t o t h r e e a r e a s , the c o s t a l s t r i p , the m i d d l e f i e l d , and the a n a l a r e a . The t h r e e s t r o n g v e i n s , the c o s t a , the s u b c o s t a and the f i r s t branch of the r a d i u s o c c u p y i n g the c o s t a l s t r i p a r e s t r e n g t h e n e d by a c o s t a l b r a c e near the wing base. These v e i n s may be broken a t t h e i r m i d p o i n t s by a b u l l a , p r o v i d i n g g r e a t e r f l e x i b i l i t y . The v e n a t i o n of the m i d d l e f i e l d c o n s i s t s o f the r a d i a l s e c t o r and media, b o t h of which a r e f o r k e d a l m o s t a t t h e i r b a s e s . The a n t e r i o r b ranch o f the r a d i a l s e c t o r i s d i c h o t o m o u s l y f o r k e d f a r t h e r o u t , and i t s p o s t e r i o r branch i s f o r k e d to form the \" o u t e r f o r k \" ( O f ) . O f t e n t h e s e f o r k s and the i n t e r c a l a r i e s between them form \" t r i a d s \" . The a n a l a r e a c o n t a i n s the c u b i t u s , which i s d i v i d e d t o i t s base, and s e v e r a l s h o r t a n a l v e i n s . The f l u t i n g o f the w i n g s , caused by the c o n v e x i t y and c o n c a v i t y of the v e i n s and t h e i r b r a n c h e s , i s c o n s t a n t and d i s t i n c t . T h i s i s an a i d to i d e n t i f i c a t i o n when the f o r k s become detached and appear t o be i n t e r c a l a r i e s - . C r o s s v e i n s a r e numerous, and s e r v e t o s t r e n g t h e n the f l u t e d arrangement of the l o n g i t u d i n a l v e i n s . They a r e p a r t i c u l a r l y s t r o n g i n the s t i g m a t i c a r e a , and may be reduced or w a n t i n g i n the b a s a l c o s t a l a r e a i n the more s p e c i a l i z e d s p e c i e s . M a r g i n a l v / e i n l e t s , v a r y i n g i n number and form, may be p r e s e n t i n some g e n e r a . The h i n d wings are s m a l l e r t h a n the f o r e w i n g s , and v a r y i n shape. They become s m a l l e r w i t h s p e c i a l i z a t i o n , and may be absent i n v e r y s p e c i a l i z e d g e n e r a . Each b e a r s a v a r i a b l e c o s t a l p r o j e c t i o n on the b a s a l c o s t a l margin which u n d e r l i e s the a n a l a r e a o f t h e f o r e w i n g , c a u s i n g b o t h wings t o move s y n c h r o n o u s l y . The v e n a t i o n i s s i m p l e r , and the Of of the Rs may be a b s e n t . C r o s s v e i n s a r e o f t e n few or a b s e n t . The l e g s a r e weak, and t h e m i d d l e and h i n d l e g s may even be v e s t i g i a l . They c o n s i s t of a s h o r t c o x a , t r o c h a n t e r , and femur, a l o n g e r t i b i a , and u s u a l l y a 5 - j o i n t e d t a r s u s . In t h e m i d d l e and h i n d l e g s t h e f i r s t one or two t a r s a l j o i n t s may be f u s e d t o the t i b i a . The f o r e l e g s a r e l o n g e r and e x t e n d f o r w a r d , t h o s e o f the male b e i n g l o n g e r t h a n t h o s e o f t h e f e m a l e , w i t h a r e v e r s i b l e j o i n t a t the t a r s a l base. The male f o r e t a r s u s i s u s u a l l y l o n g e r than the t i b i a . The p a i r e d t a r s a l c l a w s may be s i m i l a r o r d i s s i m i l a r . In the. l a t t e r case one o f each p a i r may be hooked and p o i n t e d , and the o t h e r l o b e l i k e and b l u n t . The l e g s are u s u a l l y bare o f v e s t i t u r e , and c o l o u r d i f f e r e n c e s o f the segments a r e sometimes u s e f u l taxonomic c r i t e r i a . Even more v a l u a b l e f o r t h i s purpose a re t h e p r o p o r t i o n s o f the l e g segments, p a r t i c u l a r l y o f t h e t a r s a l j o i n t s ' , which a re e x a c t and c o n s t a n t f o r each s p e c i e s , but d i f f e r between the s e x e s , and among the v a r i o u s s p e c i e s . -9-The abdomen, composed o f t e n segments, has p a i r e d g e n i t a l o p e n i n g s . The male g e n i t a l i a are e x t r e m e l y i m p o r t a n t taxonomic f e a t u r e s . The p o s t e r i o r margin of the 9 t h s t e r n i t e a r t i c u l a t e s w i t h a b r o a d , f r e e l y moveable f o r c e p s base, b e a r i n g from i t s d i s t a l a n g l e s a p a i r of 3 o r 4 - j o i n t e d g r a s p i n g f o r c e p s . The s e g m e n t a t i o n o f the f o r c e p s i s o f t e n i n c o m p l e t e and the second j o i n t i s the l o n g e s t and may bear a t u b e r c l e on i t s i n n e r m a r g i n . T h e f o r c e p s and f o r c e p s base v a r y i n shape. The p a i r e d penes, above and a r i s i n g from, the f o r c e p s base, a r e t u b u l a r e x t e n s i o n s of the sperm d u c t s . They may bear c h i t i n o u s appendages i n the form o f s t o u t , s h a r p , p o s t e r i o r l y d i r e c t e d s p u r s on the b a s a l i n n e r m a r g i n s , f l a t parameres on the o u t e r m a r g i n s , o r , as i n most of t h e L e p t o p h l e b i i n a e , l a r g e r e f l e x e d v e n t r a l s p u r s on the a p i c e s . There may a l s o be l e s s e r t e e t h , s p i n e s , and s p i n u l e s . The 9 t h s t e r n i t e o f t h e female i s e xtended back as a n o t c h e d or l o b e d s u b a n a l p l a t e . The p a i r e d o v i d u c t s , o p e n i n g between the 7 t h and 8 t h s t e r n i t e s , are c o v e r e d by the 7 t h s t e r n i t e which i s p r o d uced backwards t o form the egg v a l v e . The t a i l s are two or t h r e e i n number and v a r y i n l e n g t h . S e x u a l dimorphism may be e x h i b i t e d , i n t h a t the m i d d l e t a i l ( c a u d a l f i l a m e n t ) o f the male may be a b s e n t . The a bdominal t e r g i t e s may bear l a t e r a l e x t e n s i o n s e n d i n g i n p o s t e r o - l a t e r a l s p i n e s . The t e r g i t e s o f the t h o r a x and the abdomen v a r y i n c o l o u r and p a t t e r n among gr o u p s , but a r e c o n s t a n t f o r s p e c i e s . The a b d o m i n a l s t e r n i t e s may e x h i b i t g a n g l i o n i c m a r k i n g s . -18-The nymphs v a r y i n form from the s t r e a m - l i n e d , l a t e r a l l y c ompressed, s l e n d e r , h a i r l e s s free-swimming s p e c i e s t o the s p r a w l i n g , d e p r e s s e d , s e t a c i o u s , mud and s i l t d w e l l e r s . The head, t h o r a x and abdomen may bear s p i n e s , as i n the E p h e m e r e l l a . The head v a r i e s i n shape from h i g h and narrow to t h e f l a t , d e p r e s s e d shape found i n the H e p t a g e n i i n a e . I f a f r o n t a l p r o c e s s i s p r e s e n t i t v a r i e s i n shape. The antennae are l o n g e r than t h o s e o f the a d u l t , and are f i l i f o r m . The compound eyes are l a t e r a l i n p o s i t i o n i n the b u r r o w e r s and f r e e swimming g r o u p s , but d o r s a l i n the f l a t t e n e d s p e c i e s . The t h r e e o c e l l i a r e d i r e c t e d f o r w a r d i n the f r e e swimmers, and d o r s a l l y i n the s p r a w l e r s . The mouthparts of the nymphs a r e t y p i c a l of chewing i n s e c t s , w i t h a few m o d i f i c a t i o n s . The s i m p l e , q u a d r a t e labrum may bear s p i n e s , and may be n o t c h e d , e m a r g i n a t e , or b e a r i n g a f r i n g e o f h a i r s on i t s a n t e r i o r m a r g i n . The a s s y m e t r i c a l m a n d i b l e s each bear two t o o t h e d c a n i n e s a p i c a l l y and a g r i n d i n g molar s u r f a c e . Between t h e s e i s a s m a l l p r o s t h e c a . A r i s i n g from'the o u t e r s u r f a c e o f each mandible i n the Ephemeridae i s a l o n g , upward c u r v e d , b l a d e -l i k e t u s k . The o u t e r c a n i n e s i n the P a r a l e p t o p h l e b i a are extended as l o n g , b l u n t t u s k s d i r e c t e d o b l i q u e l y upward. The c a r d o and s t i p e s of each m a x i l l a are d i s c r e e t a r e a s , but t h e g a l e a and l a c i n i a . a r e f u s e d . The m a x i l l a e may bear t e e t h , b r i s t l e s , or a \"diatom r a k e \" on the crown ( A m e l e t u s ) . The p a l p i a r e u s u a l l y 3 - j o i n t e d . The l a b i u m i s of the u s u a l form, w i t h l o n g , w e l l s e p a r a t e d g l o s s a e and p a r a g l o s s a e . The l a b i a l p a l p i are o r d i n a r i l y 2 or 3 - j o i n t e d . The l e g s o f t h e nymph are s h o r t e r t h a n t h o s e o f the a d u l t . The femora may be f l a t t e n e d i n the s p r a w l i n g f o r m s , and may bear s p i n e s o r h a i r s . The t a r s i a r e 1 - j o i n t e d and bear s i n g l e c l a w s which may be d e n t i c u l a t e and which vary i n form. The l a m e l l a t e , f i l a m e n t o u s , o r plumose g i l l s a r i s e l a t e r a l l y from a l l o r some of the f i r s t seven abdominal segments, and some s p e c i e s a l s o bear plumose g i l l s a t the bases of the coxae, and t h e m a x i l l a e . The g i l l s may be doub l e or s i n g l e and are d i r e c t e d l a t e r a l l y , d o r s a l l y , o r v e n t r a l l y , and sometimes o v e r l a p each o t h e r to form- a s t r o n g s u c k e r d i s c . The g i l l s o f some groups a r e h e a v i l y c h i t i n i z e d on the a n t e r i o r m a r g i n s , or f r i n g e d w i t h h a i r s on the p o s t e r i o r m a r g i n s , as i n the genus C a e n i s . In o t h e r g r o u p s , n o t a b l y the C a e n i s . T r i c o r y t h o d e s , and some E p h e m e r e l l a , the f i r s t p a i r o f g i l l s a r e o p e r c u l a t e . T r a c h e a t i o n o f the g i l l s , i f c o n s p i c u o u s , i s s i m p l e , p a l m a t e , or p e c t i n a t e . The t a i l s are two or t h r e e i n number. The f r e e swimming groups found i n s t i l l w a t e r , s u c h as the S i p h l o n u r u s , B l a s t u r u s , and C a l l i b a e t i s , and - a l s o the Ameletus i n streams bear a heavy f r i n g e of h a i r s on the i n n e r s u r f a c e o f each l a t e r a l t a i l , and on both s i d e s o f the m i d d l e t a i l . The b u r r o w e r s and s p r a w l e r s have bare t a i l s , perhaps w i t h w h o r l s o f a few h a i r s at the j o i n i n g s of the t a i l segments. The t a i l s may be u n i c o l o u r o u s o r banded. The c o l o u r and p a t t e r n of the t e r g i t e s and l e g s . v a r i e s g r e a t l y among groups, but i s c o n s t a n t f o r each s p e c i e s . -12-CHECKLI5T OF THE EMPHEMEROPTERA OF BRITISH COLUMBIA Order Ephemeroptera S u p e r f a m i l y H e p t a g e n i o i d e a F a m i l y S i p h l o n u r i d a e S u b f a m i l y : S i p h l o n u r i n a e Ameletus c e l e r McDunnough Ameletus c e l e r o i d e s McDunnough Ameletus c o n n e c t i n a fYlcDunnough Ameletus c o o k i McDunnough Ameletus monta Mayo Ameletus o r e q o n e n s i s McDunnough Ameletus q u e r u l u s McDunnough Ameletus s i m i l i o r McDunnough Ameletus s p a r s a t u s McDunnough Ameletus s u f f u s u s McDunnough Ameletus t u b e r c u l a t u s McDunnough Ameletus v a l i d u s McDunnough A m e l e t i s v a n c o u v e r e n s i s McDunnough Ameletus v e r n a l i s McDunnough Ameletus s p . 1 * * U n t i l f u r t h e r i n v e s t i g a t i o n o f u n i d e n t i f i e d specimens can be u n d e r t a k e n , they have been numbered, r a t h e r than named by the a u t h o r . -13-P a r a m e l e t u s c o l u m b i a e lYlcDunnough S i p h l o n u r u s a u t u m n a l i s fflcDunnough S i p h l o n u r u s columbianus lYlcDunnough S i p h l o n u r u s o c c i d e n t a l i s Eaton S i p h l o n u r u s s p . 1 S i p h l o n u r u s sp. 2 S i p h l o n u r u s sp. 3 S i p h l o n u r u s sp. 4 S i p h l o n u r u s sp. 5 S i p h l o n u r u s s p . 6 S i p h l o n u r u s s p . 7 S i p h l o n u r u s sp. 8 S i p h l o n u r u s sp. 9 F a m i l y H e p t a g e n i i d a e S u b f a m i l y H e p t a g e n i i n a e Cinyqma i n t e g r u m Eaton Cinyqmula q a r t r e l l i lYIcDunnough Cinyqmula k o o t e n a i ItlcDunnough Cinyqmula mimus ( E a t o n ) Cinyqmula par ( E a t o n ) Cinyqmula r a m a l e y i (Dodds) Cinyqmula u n i f o r m i s (fflcDunnough) Cinyqmula sp. 1 .. .. -14-Epeorus d e c e p t i v u s (McDunnough) Epeorus d u l c i a n a McDunnough Epeorus f l a v / i p e n n i s T r a v e r Epeorus q r a n d i s (McDunnough) Epeorus lonqimanus Eaton Epeorus permaqnus T r a v e r Epeorus s p. 1 Epeorus sp. 2 Epeorus sp. 3 Epeorus sp. 4 Epeorus sp. 5 H e p t a q e n i a e l e q a n t u l a ( E a t o n ) H e p t a q e n i a s i m p l i c o i d e s McDunnough H e p t a q e n i a s o l i t a r i a McDunnough H e p t a q e n i a sp. 1 H e p t a q e n i a s p. 2 H e p t a q e n i a sp. 3 H e p t a q e n i a sp. 4 H e p t a q e n i a s p. 5 H e p t a q e n i a sp. 6 H e p t a q e n i a sp. 7 H e p t a q e n i a sp. 8 R i t h r o q e n a d o d d s i McDunnough R i t h r o q e n a .je.juna Eaton R i t h r o q e n a m o r r i s o n i Banks R i t h r o q e n a r o b u s t a Dodds -15-R i t h r o q e n a v i r i l i s WcDunnough R i t h r o q e n a s p. 1 R i t h r o q e n a s p. 2 R i t h r o q e n a s p . 3 Stenonema terminatum (U/alsh) F a m i l y Ametropodidae S u b f a m i l y ffletretopodinae fflet r e t o p u s b o r e a l i s Eaton F a m i l y B a e t i d a e S u b f a m i l y B a e t i n a e B a e t i s b i c a u d a t u s Dodds B a e t i s i n s i q n i f i c a n s fflcDunnough B a e t i s i n t e r m e d i u s Dodds B a e t i s .jssmondensis fflcDunnough B a e t i s p a r v u s Dodds B a e t i s p e r s e c u t a (IflcDunnough B a e t i s sp. 1 B a e t i s s p . 2 : B a e t i s sp. 3 B a e t i s sp. 4 B a e t i s sp. 5 B a e t i s sp. 6 B a e t i s s p . 7 C a l l i b a e t i s c a r o l u s T r a v e r C a l l i b a e t i s c o l o r a d e n s i s Banks C a l l i b a e t i s h a g e n i ( E a t o n ) -16-C a l l i b a e t i s s p . 1 C a l l i b a e t i s sp. 2 C a l l i b a e t i s s p . 3 C a l l i b a e t i s s p . 4 C a l l i b a e t i s s p . 5 C a l l i b a e t i s s p . 6 C a l l i b a e t i s s p . 7 C a l l i b a e t i s s p . 8 C e n t r o p t i l u r n album 1 C e n t r o p t i l u m b e l l u m C e n t r o p t i l u m b i f u r c a t u m McDunnough C e n t r o p t i l u m conturbatum McDunnough C e n t r o p t i l u m s p . 1 C e n t r o p t i l u m sp. 2 C e n t r o p t i l u m s p . 3 C e n t r o p t i l u m s p . 4 \u00E2\u0080\u00A2 Meocloeon : sp. 1 S u p e r f a m i l y L e p t o p h l e b i o i d e a F a m i l y L e p t o p h l e b i i d a e S u b f a m i l y L e p t o p h l e b i i n a e L e p t o p h l e b i a s p . 1 L e p t o p h l e b i a s p . 2 B l a s t u r u s c u p i d u s (Day) B l a s t u r u s q r a v a s t e l l a ( E a t o n ) -17-B l a s t u r u s n s b u l o s u s (UJalker) B l a s t u r u s sp\u00E2\u0080\u00A2 1 P a r a l e p t o p h l e b i a b i c o r n u t a (fflcDunnough) P a r a l e p t o p h l e b i a d e b i l l s (UJalker) P a r a l e p t o p h l e b i a q r e q a l i s ( E a t o n ) P a r a l e p t o p h l e b i a h e t e r o n e a (fflcDunnough) P a r a l e p t o p h l e b i a p a l l i p e s (Hagen) P a r a l e p t o p h l e b i a r u f iv/enosa .(Eaton) P a r a l e p t o p h l e b i a t e m p o r a l i s (fflcDunnough) P a r a l e p t o p h l e b i a v a c i v a ( E a t o n ) P a r a l e p t o p h l e b i a s p. 1 P a r a l e p t o p h l e b i a sp'. 2 P a r a l e p t o p h l e b i a sp.\u00E2\u0080\u00A23 - P a r a l e p t o p h l e b i a s p. 4 P a r a l e p t o p h l e b i a sp. 5 F a m i l y E p h e m e r e l l i d a e S u b f a m i l y E p h e m e r e l l i n a e E p h e m e r e l l a c o l o r a d e n s i s Dodds E p h e m e r e l l a d o d d s i Weedham E p h e m e r e l l a f l a v / i l i n e a fflcDunnough E p h e m e r e l l a q r a n d i s i n q e n s fflcDunnough E p h e m e r e l l a hecuba hecuba Eaton E p h e m e r e l l a h e t e r o c a u d a t a fflcDunnough -18-E p h e m e r e l l a h y s t r i x T r a v e r E p h e m e r e l l a i n e r m i s Eaton E p h e m e r e l l a i n f r e q u e n s McDunnough E p h e m e r e l l a j a c o b i McDunnough E p h e m e r e l l a l o d i Mayo E p h e m e r e l l a s p i n i f e r a Needham E p h e m e r e l l a t e r e s a T r a v e r E p h e m e r e l l a t i b i a l i s McDunnough E p h e m e r e l l a sp. 1 F a m i l y T r i c o r y t h i d a e S u b f a m i l y L e p t o h y p h i n a e T r i c o r y t h o d e s minutus T r a v e r T r i c o r y t h o d e s s p . 1 S u p e r f a m i l y Caenoidea F a m i l y Caenidae S u b f a m i l y Caeninae C a e n i s sp. 1 C a e n i s s p . 2 C a e n i s s p . 3 C a e n i s s p . 4 S u p e r f a m i l y Ephemeroidea F a m i l y Ephemeridae S u b f a m i l y Ephemerinae Ephemera s i m u l a n s UJalker -19-Hexaqenia l i m b a t a ( G u e r i n ) P e n t a q e n i a sp. 1 -20-O R D E R E P H E M E R O P T E R A KEY TO ADULTS 1. V e i n s M and C u l s t r o n g l y d i v e r g e n t a t base, w i t h IYI2 s t r o n g l y bent toward the Cu b a s a l l y S u p e r f a m i l y Ephemeroidea V e i n s M and C u l l i t t l e d i v e r g e n t a t base and the f o r k o f M more n e a r l y s y m m e t r i c a l 2. 2. T a i l s two. H i n d t a r s i 4 o r 5 - j o i n t e d . S u p e r f a m i l y H e p t a q e n i o i d e a T a i l s t h r e e . H i n d t a r s i 4 - j o i n t e d 3. 3. F o r c e p s 1 - j o i n t e d . P rosternum 2 or 3 tim e s l o n g e r than b r o a d , so t h a t the coxae a r e ver y c l o s e t o g e t h e r S u p e r f a m i l y Caenoidea F o r c e p s 3 or 4 - j o i n t e d . P rosternum not as above . S u p e r f a m i l y L e p t o p h l e b i o i d e a KEY TO NYMPHS 1. M a n d i b l e s each w i t h an e x t e r n a l t u s k p r o j e c t i n g f o r w a r d and v i s i b l e d o r s a l l y . Head w i t h a c o n s p i c u o u s f r o n t a l p r o c e s s between the bases o f t h e a n t e n n a e . . S u p e r f a m i l y Ephemeroidea M a n d i b l e s with'no e x t e r n a l t u s k s , o r i f p r e s e n t , d e p r e s s e d , and head w i t h no f r o n t a l p r o c e s s between the bases o f t h e antennae . 2. 2. Outer t a i l s f r i n g e d on the i n n e r s i d e o n l y , perhaps w i t h a few s h o r t h a i r s on the o u t e r s i d e . T a i l s may not be f r i n g e d , but may bear w h o r l s of s p i n e s a t each t a i l j o i n i n g . I f t h i s i s s o , the head i s s t r o n g l y d e p r e s s e d , w i t h eyes and antennae d o r s a l . T a i l s may be two . S u p e r f a m i l y H e p t a q e n i o i d e a -21-Outer t a i l f r i n g e d on both s i d e s , o r i f not f r i n g e d , t a i l s u i i t h w h o r l s of s p i n e s a t each j o i n i n g . In the l a t t e r c a s e , the g i l l s o f the second abdominal segment are e l y t r o i d . . . . 3 . G i l l s o f the second abdominal segment e l y t r o i d , q u a d r a t e , and the g i l l s on segments 3-6 have d e e p l y f r i n g e d m a r g i n s . A l l g i l l s s i n g l e S u p e r f a m i l y Caenoidea G i l l s not e l y t r o i d , o r i f g i l l s o f second abdominal segment are e l y t r o i d , t h e y are t r i a n g u l a r ; the margins of the g i l l s on segments 3-6 are not f r i n g e d , and a l l g i l l s a r e d o u b l e . . . S u p e r f a m i l y L e p t o p h l e b i o i d e a SUPERFAIMLY HEPTAGENIOIDEA Key to A d u l t s H i n d t a r s i 5 - j o i n t e d . Eyes of male not t u r b i n a t e . Outer f o r k o f Rs of h i n d wing p r e s e n t or a b s e n t . Wore than 2 c u b i t a l i n t s r c a l a r i e s i n f o r e w i n g 2. Hind t a r s i 4 - j o i n t e d . Eyes o f male t u r b i n a t e . Outer f o r k o f Rs of h i n d wing a b s e n t . Four l o n g c u b i t a l i n t e r c a l a r i e s i n f o r e w i n g . Hind wing may be absent . F a m i l y B a e t i d a e , S u b f a m i l y B a e t i n a e C u b i t a l i n t e r c a l a r i e s i n 2 p a r a l l e l p a i r s , l o n g and s h o r t a l t e r n a t i n g . Eyes of male s i m p l e . Outer f o r k of Rs i n h i n d wing p r e s e n t or a b s e n t . . . F a m i l y H e p t a q e n i i d a e , S u b f a m i l y H e p t a q e n i i n a e C u b i t a l i n t e r c a l a r i e s of f o r e w i n g not as above. Eyes of male e n t i r e , h o r i z o n t a l l i n e on s u r f a c e m a r k i n g o u t 2 a r e a s . Outer f o r k o f Rs i n h i n d wing p r e s e n t . -..3. -22-3. C u b i t a l i n t e r c a l a r i e s of f o r e w i n g c o n s i s t of a s e r i e s of f o r k i n g or s i n u a t e v e i n l e t s a t t a c h i n g C u l t o h i n d m a r g i n . . F a m i l y S i p h l o n u r i d a e , S u b f a m i l y S i p h l o n u r i n a e C u b i t a l i n t e r c a l a r i e s of f o r e w i n g 2-4 i n number, f r e e b a s a l l y , not f o r k i n g or. s i n u a t e F a m i l y JAmetropodidae, S u b f a m i l y ffletretopodinae Key To Nymphs . Nymph d e p r e s s e d . Eyes and antennae d o r s a l . G i l l s of a s i n g l e l a m e l l a , u s u a l l y w i t h a f i b r i l l i f o r m t u f t a t or near the base F a m i l y H a p t a q e n i i d a e , S u b f a m i l y H e p t a q e n i i n a e Nymph not d e p r e s s e d . Eyes and/or antennae l a t e r a l , a n t e r o -l a t e r a l , or a n t e r i o r . G i l l l a m e l l a e double o r s i n g l e 2. Claws of f o r e l e g b i f i d . Claws of m i d d l e h i n d l e g s l o n g and s l e n d e r , about as l o n g as t h e s h o r t t i b i a F a m i l y Ametropodidae, S u b f a m i l y lYletretopodinae Claws s i m i l a r , s h a r p - p o i n t e d , much s h o r t e r t h a n t i b i a . Claws o f m i d d l e and h i n d l e g s may be l o n g and s l e n d e r , of f o r e l e g s s h o r t , 3. 3. P o s t e r o - l a t e r a l a n g l e s of the a p i c a l a bdominal segments p r o l o n g e d i n t o t h i n f l a t l a t e r a l s p i n e s - i f weak, antennae l e s s than t w i c e the w i d t h of the head. V a r i a b l e appendage on f o r e coxa F a m i l y S i p h l o n u r i d a e , S u b f a m i l y S i p h l o n u r i n a e P o s t e r o - l a t e r a l a n g l e s of a p i c a l abdominal segments h a r d l y more than a c u t e , not p r o l o n g e d i n t o f l a t t h i n l a t e r a l s p i n e s s o , i f weak, antennae mors t h a n t w i c e the w i d t h o f the head. No appendage ..on f o r e coxa F a m i l y B a e t i d a e , S u b f a m i l y B a e t i n a e 1. 2. -23-SUBFAiTlILY 5IPHL0NURINAE ADULT Fore wing narrowed j u s t beyond the base and widened somewhat a t the a n a l a n g l e , r e l a t i v e l y l o n g f o r i t s w i d t h ; the a n t e r i o r b ranch of the. c u b i t a l v e i n i s a t t a c h e d to the i n n e r margin by a s e r i e s of c r o s s - v e i n s , which a r e o f t e n f o r k e d and s i n u a t e ; the h i n d wing i s a l m o s t o r f u l l y as wide as l o n g , the a n a l r e g i o n w e l l - d e v e l o p e d ; the c o s t a l p r o j e c t i o n i s not e s p e c i a l l y p r o m i n e n t , u s u a l l y somewhat o b t u s e ; the t a r s i are f i v e - j o i n t e d ; the b a s a l j o i n t s o f the m i d d l e and h i n d t a r s i are more o r l e s s c o m p l e t e l y f u s e d w i t h the t i b i a e ; a l l j o i n t s o f ' t h e male f o r e t a r s u s f r e e and movable, the f i r s t j o i n t a t l e a s t l / 3 the l e n g t h of t h e second j o i n t , and may e q u a l o f exceed i t ; t he f o r c e p s . a r e more o r l e s s d i s t i n c t l y f o u r - j o i n t e d ; the f o r c e p s base i s u s u a l l y v e r y l o n g , more or l e s s d e e p l y e m a r g i h a t e i n i t s a p i c a l m a r g i n , between the f o r c e p s l i m b s ; b a s a l j o i n t i s u s u a l l y r i n g - l i k e , o f t e n f u s e d w i t h the second j o i n t , which i s o f t e n s t r o n g l y bowed; two ( o r r a r e l y t h r e e ) t e r m i n a l j o i n t s , t o g e t h e r not l o n g e r than the second. In Ameletus, s u b a n a l p l a t e o f female more o r l e s s d e e p l y c a r v e d out i n the a p i c a l m a r g i n , convex i n o t h e r g e n e r a ; two t a i l s . NYMPH Body s t r e a m - l i n e d , much compressed; head i n f l e x e d ; l e g s l o n g ; c l a w s l o n g and s l e n d e r , , not. d e n t i c u l a t e ; l a t e r a l margins of a p i c a l a bdominal t e r g i t e s expanded i n t o f l a t l a t e r a l e x t e n s i o n s , l e s s so i n Ameletus; a s p i n e on the p o s t e r o - l a t e r a l a n g l e o f each m i d d l e and a p i c a l t e r g i t e ; g i l l s on segments 1-7, s i m p l e and s i n g l e , e x c e p t -24-i n S i p h l o n u r u s where g i l l s a r e double and l a m e l l a t e , p a r t s s i m i l a r ; t h r e e t a i l s , m i d d l e one h e a v i l y f r i n g e d on each s i d e , l a t e r a l ones on i n n e r m a rgins o n l y . SUBFAMILY SIPHLONURINAE Key To A d u l t s 1. Claws of each t a r s u s d i s s i m i l a r . C o s t a l a n g u l a t i o n of h i n d wing a c u t e . Fork of M d e t a c h e d . Subanal p l a t e concave.. \u00E2\u0080\u00A2Ameletus Eaton Claws a l l s h a r p - p o i n t e d . C o s t a l a n g u l a t i o n o f h i n d wing o b t u s e . Fork of M not d e t a c h e d . Subanal p l a t convex 2. 2. H i n d t a r s u s s h o r t e r than or s u b e q u a l to t i b i a . P o s t e r i o r branch of M forms a l m o s t a r i g h t a n g l e a t i t s u n i o n w i t h the stem.. P a r a m e l e t u s Bengtsson H i n d t a r s u s l o n g e r than t i b i a . Fork o f ffl n o r m a l . S i p h l o n u r u s Eaton Key To Nymphs 1. G i l l l a m e l l a e s i n g l e on a l l segments 2. G i l l l a m e l l a e double on segments one and two, and sometimes on o t h e r segments. L a m e l l a e e q u a l i n s i z e . S i p h l o n u r u s Eaton 2. A f r i n g e o f p e c t i n a t e s p i n e s on crown of g a l e a - l a c i n i a . No p i n c e r l i k e p r o c e s s on t i p of l a b i a l p a l p Ameletus Eaton No p e c t i n a t B s p i n e s on crown of g a l e a - l a c i n i a . A p i n c e r - l i k e p r o c e s s hear t i p of l a b i a l p a l p . . . . . , P a r a m e l e t u s Bengtsson -25-GENUS AHOELETUS EATON Ameletus, Needham, 1935, The B i o l o g y of M a y f l i e s , 446, ( B i b l i o g r a p h y ) A d u l t ; Medium s i z e d , b r o w n i s h or y e l l o w brown, abdomen of female o f t e n d a r k e r than t h a t of male; v e r t e x and o c c i p u t o f female u s u a l l y w i t h dark submedian marks; h i n d margin of head s l i g h t l y concave; eyes of male l a r g e ; u s u a l l y c o n t i g u o u s above, not d i v i d e d , a t r a n s -v e r s e band of p a l e r c o l o u r may ext e n d o b l i q u e l y a c r o s s the o u t e r s u r f a c e ; f o r e w i n g t h r e e t i m e s as l o n g as wide; h i n d wing w e l l -d e v e l o p e d , c o s t a l a n g u l a t i o n a c u t e ; median v e i n o f h i n d wing f o r k e d near base; v e n a t i o n dark; ;. humeral c r o s s v e i n s t r o n g and d a r k ; many c r o s s v e i n s i n c o s t a l h a l f o f f o r e w i n g may be brown-margined, so t h a t wing l o o k s s p e c k l e d ; s t i g m a t i c c r o s s v e i n s u s u a l l y f o r k e d and anastamosed; f o r e l e g o f male as l o n g as body; f i r s t f o r e t a r s a l j o i n t l / 3 t o l / 2 as l o n g as second; a l l c l a w s d i s s i m i l a r ; abdominal t e r g i t e s u s u a l l y w i t h wide dark p o s t e r i o r m a r g i n s , p o s t e r o - l a t e r a l a n g l e s , and e x t e n s i o n s a l o n g p l e u r a l f o l d ; s t e r n i t e s o f t e n w i t h b l a c k o r brown g a n g l i o n i c marks; f o r c e p s base w i t h a t u b e r c l e o r p r o j e c t i o n on each s i d e o f a p i c a l e x c a v a t i o n ; two t e r m i n a l j o i n t s , s h o r t e r t o g e t h e r t h a n second j o i n t ; penes l o n g and s l e n d e r , may be w i t h s p i n e s on i n n e r m a r g i n , and t i p s may be seen beyond f o r c e p s p l a t e , when viewed from b e n e a t h . Nymphs; ( T i a x i l l a r y and l a b i a l p a l p s t h r e e - j o i n t e d , f o r m e r s h o r t and weak; m a x i l l a w i t h a broad crown, b e a r i n g l o n g p e c t i n a t e s p i n e s ; m a n d i b l e s t r i a n g u l a r , w i t h c a n i n e s a t one p o i n t and molar s u r f a c e a t a n o t h e r ; -26-labrum a l i t t l e l o n g e r than wide, e m a r g i n a t e on f r o n t a l b o r d e r ; l e g s r a t h e r s h o r t ; p o s t e r o - l a t e r a l s p i n e s u s u a l l y on segments 4-9, but s h o r t and weak on segments 4-6; the l a t e r a l margins on t h e s e o n l y v e r y s l i g h t l y compressed; g i l l s s i n g l e , s i m p l e , s m a l l and o v a l ; t a i l s u s u a l l y w i t h a wide dark t r a n s v e r s e band a t m i d d l e and a narrow one a t apex. Genotype: Ameletus s u b n o t a t u s E a t o n . AfflELETUS Key To A d u l t s 1. C r o s s v e i n s f a i n t l y or s t r o n g l y marked w i t h brown to b l a c k 2. No m a r g i n a l c r o s s v e i n s . . . . 8. 2. G a n g l i o n i c markings dark 3. No dark g a n g l i o n i c m a r k i n g s . . .7. 3. A n t e r i o r t w o - t h i r d s of abdominal t e r g i t e s h y a l i n e w h i l e p o s t e r i o r o n e - t h i r d deep brown. Wings h y a l i n e 4. Wings c l o u d y or t i n t e d 5. 4. C r o s s v e i n s dark e x c e p t i n c o s t a - b a s a l a r e a . . . . . . . . c o n n e c t i n a iYlcD C r o s s v e i n s i n c o n s p i c u o u s and o n l y f a i n t l y shaded t u b e r c u l a t u s ItlcD 5. Wings not t i n g e d , a l t h o u g h c l o u d s p r e s e n t i n wings. Abdominal t e r g i t e s deep brown s i m i l i o r IflcD Wings t i n g e d . Abdominal t e r g i t e s l i g h t - c o l o u r e d ..6. 6. Wings w i t h r e d d i s h brown t i n g e . Abdominal t e r g i t e 1 dark brown, r e s t s e m i - h y a l i n e .monta fflayo Wings of male a m b e r - t i n g e d . C l o u d s i n w i n g s . Abdominal -27-t e r g i t e s y e l l o w - b r o w n s p a r s a t u s fflcD 7. UJings t i n g e d w i t h umber brown, p a l i n g somewhat o u t w a r d l y . Abdom-i n a l t e r g i t e 1 b l a c k , o t h e r s b r i g h t y e l l o w b o r d e r e d p o s t e r i o r l y w i t h brown . . . s u f f u s u s lYlcD UJings not t i n g e d , a l t h o u g h c l o u d y . Abdominal t e r g i t e s p i n k i s h brown . v a l i d u s fflcD 8. G a n g l i o n i c a r e a s marked w i t h orange to b l a c k ...9. No g a n g l i o n i c m arkings 12. 9. Wings not t i n g e d . . . . 10. LUings f a i n t l y smoksyor grey t i n g e d . Not s p e c k l e d or c l o u d y c e l e r fflcD 10. G a n g l i o n i c m arkings dark brown .....11. G a n g l i o n i c m a r k i n g s orange. c o o k i fflcD 11. Two s m a l l s p i n e s on i n n e r margin of each d i v i s i o n o f penes. Abdominal t e r g i t e s 2 to 7 y e l l o w i s h brown.... . c e l e r o i d e s IflcD S i n g l e l o n g s l e n d e r s p i n e on i n n e r m a r g i n of each d i v i s i o n , o f the penes. Abdominal t e r g i t e s 2 to. 7 g r e y i s h w h i t e . v e r n a l i s lYlcD 12. UJings t i n g e d w i t h brown, umber brown, or amber 13. UJings p a l e h y a l i n e q u e r u l u s BlcD 13. UJings t i n g e d e n t i r e l y or i n p a r t w i t h brown o r umber brown...14. UJings e n t i r e l y t i n g e d w i t h amber , .sp. 1 14. Wings t i n g e d . w i t h brown a t base. Abdominal t e r g i t e s y e l l o w -w h i t e o r e q o n e n s i s fflcD Wings s t r o n g l y and e n t i r e l y t i n g e d w i t h umber brown. Abdominal t e r g i t e s y e l l o w brown v a n c o u v e r e n s i s (Y!cD -28-Key To Nymph 1. Ta i J s p a l e ochreous . c e l e r UllcD T a i l s w i t h one or more dark bands, i n one or more of the t h r e e t a i l s 2. 2. M i d d l e t a i l p a l e r than o u t e r t a i l s , w hich are l i g h t brown. M i d d l e t a i l w i t h a f a i n t brown narrow band i n m i d d l e v a l i d u s McD A l l t h r e e t a i l s s i m i l a r l y marked 3. 3. T a i l s w i t h s i n g l e median, dark band and dark t i p s 4. T a i l s w i t h s i n g l e median dark band, but p a l e b a s a l l y and a p i c a l l y \u00E2\u0080\u00A2 6. 4. V e n t r a l l y on f i r s t s even segments t h e r e i s a broad dark broken m e d i o - v e n t r a l band, t a p e r i n g c e p h a l a d on each segment to a p o i n t and not q u i t e a t t a i n i n g a n t e r i o r m a r g i n , but b r o a d e n i n g out i n p o s t e r i o r h a l f of segments, e s p e c i a l l y of segments 5 and 6, where i t a l m o s t c o e l e s c e s w i t h a dark l a t e r a l s t r i p e , e x t e n d i n g down segments s l i g h t l y - i n t e r i o r t o p a l e edges. Segments 8 and 9 brown w i t h s m a l l w h i t e s p o t s on a n t e r i o r margin s u f f u s u s McD U e n t r a l l y p a l e brown w i t h b r o a d l y p a l e l a t e r a l edges, e x c e p t on segment 9 and a s m a l l p a l e dot near a n t e r o - l a t e r a l c o r n e r . 5. 5. G i l l s p a l e w i t h f a i n t t r a c h e a t i o n . An i n t e r i o r dark band j u s t w i t h i n the d o r s a l margin a n d . f a i n t t r a c e s o f c h i t i n o u s t h i c k e n i n g a l o n g v e n t r a l edge v e r n a l i s McD -29-T r a c h e a t i o n more d i s t i n c t but s t i l l not p r o m i n e n t . I n t e r i o r dark band i s c l o s e r t o d o r s a l margin, t h a n p r e v i o u s l y , and t h i c k e n i n g a l o n g v e n t r a l edge i s h e a v i e r c o n n e c t i n a iYlcD 6. No dark i n t e r i o r c h i t i n o u s band on g i l l s 7. A dark i n t e r i o r o r d o r s a l band of c h i t i n on g i l l s 8. 7. T r a c h e a t i o n o f g i l l s s p a r c e , i n d i s t i n c t c e l e r o i d e s M c D T r a c h e a t i o n o f g i l l s ' p l e n t i f u l , d i s t i n c t . s p a r s a t u s IKlcD 8. V e n t r a l l y p a l e brown.with no p a t t e r n o r e q o n e n s i s IYlcD V e n t r a l l y p a l e w i t h v a r i o u s dark p a t t e r n s 9. 9. C h i t i n o u s t h i c k e n i n g a l o n g d o r s a l and v e n t r a l edge o f g i l l s . . . . , . s i m i l i o r fflcD C h i t i n o u s band w i t h i n d o r s a l edge of g i l l s . . . 10. 10. C h i t i n o u s band near d o r s a l edge of g i l l s c o o k i IYlcD C h i t i n o u s band w e l l w i t h i n d o r s a l edge of g i l l s . 11. 11. C h i t i n o u s band o f g i l l s e x t e n d s o n l y 2/3 t o t i p of g i l l . . . q u e r u l u s IYlcD. C h i t i n o u s band of g i l l s as f a r from d o r s a l edge as w i d t h o f base of g i l l monta Mayo Unknown . Ameletus v a n c o u v e r e n s i s IYlcD Ameletus t u b e r c u l a t u s IYlcD AIYIELETUS CELER RlcDUNNOUGH Ameletus c e l e r McDunnough, Needham, 1935, The B i o l o g y of M a y f l i e s , 451 ( B i b l i o g r a p h y ) A d u l t s ; . . . . . . . . Head and t h o r a x b l a c k i s h brown, \u00E2\u0080\u00A2 abdomen y e l l o w i s h brown; -30-wings d u l l h y a l i n e , f a i n t l y smoky o r g r e y - t i n g e d , not s p e c k l e d or c l o u d y ; l o n g i t u d i n a l v e i n s and c r o s s v e i n s f i n e and brou/n; abdominal t e r g i t e s 2-7 s e m i - h y a l i n e , p a l e y e l l o w i s h - b r o w n ; p o s t e r i o r m a r gins dark brown w i t h narrow brown submedian s t r e a k s e x t e n d i n g f o r w a r d , and not a t t a i n i n g a n t e r i o r m a r g i n ; t e r g i t e s 8-10 opaque, d a r k e r ; s t e r n i t e s p a l e r , g a n g l i o n i c a r e a s marked w i t h b r o w n i s h b l a c k ; t a i l s w h i t i s h and smoky, j o i n i n g s b l a c k i s h brown; penes w i t h s e v e r a l s m a l l s p i n e s on i n n e r margin of each d i v i s i o n . Nymph: T a r s i w i t h deep brown d i s t a l bands o n l y ; no dark l o n g i t u d i n a l s t r i p e s on v e n t e r o f the abdomen; g a n g l i o n i c m a r k i n g s p r e s e n t ; t r a c h e a t i o n o f g i l l s s p a r s e and i n d i s t i n c t , no dark i n t e r i o r c h i t i n o u s band; t a i l s p a l e o c h r e o u s . D i s t r i b u t i o n : B r i t i s h C o l u m b i a , A l b e r t a . No specimens o f t h i s s p e c i e s were examined. AMELETUS CELEROIDES McDUNNOUGH Ameletus c e l e r o i d e s McDunnouqh, Needham, 1935, The B i o l o g y of May-f l i e s , 451 ( B i b l i o g r a p h y ) A d u l t : T h i s s p e c i e s i s s i m i l a r to A_;_ c e l e r , but s m a l l e r and p a l e r ; p o s t e r o - l a t e r a l a r e a of pronotum creamy; wings not smoky; a n t e r i o r p o r t i o n s of t e r g i t e s creamy, e s p e c i a l l y l a t e r a l l y on segments 6-8, and a l s o on s t e r n i t e s 7 and 8, and a p a l e creamy l i n e on l a t e r a l edge of s t e r n i t e 9; g a n g l i o n i c m a r k i n g s dark brown; penes w i t h two -31-s m a l l s p i n e s on i n n e r margin o f each d i v i s i o n ; penes l o b e s b r o a d l y d i v e r g e n t a p i c a l l y ; a l l f o r c e p s j o i n t s s l e n d e r . Nymph: S i m i l a r t o Pu_ c e l e r , but t a r s i dark banded b a s a l l y as w e l l as d i s t a l l y ; t a i l s p a l e a t base and apex, w i t h a broad dark median band. D i s t r i b u t i o n : B r i t i s h C o l u m b i a , A l b e r t a . No specimens o f t h i s s p e c i e s were examined. AMELETUS CONNECTINA McDUNNOUGH Ameletus c o n n e c t i n a McDunnouoh. McDunnough, 1939, Can. E n t . 71:50 ( B i b l i o g r a p h y ) ' A d u l t : Uiings h y a l i n e w i t h v e i n s and f i n e c r o s s v e i n s d a r k , e x c e p t i n c o s t a - b a s a l a r e a ; abdomen d o r s a l l y w i t h the a n t e r i o r 2/3 of t e r g i t e s d u l l ; - d i r t y w h i t i s h , v e i n e d w i t h d a r k e r and w i t h t r a c e s of two broken s u b d o r s a l l i n e s ; t he p o s t e r i o r l / 3 d u l l b l a c k - b r o w n ; s t e r n i t e s w i t h dark g a n g l i o n i c m a r k i n g s . Nymph: Femora p a l s w i t h a l a r g e r e c t a n g u l a r brown p a t c h i n the median a r e a , w i t h s m a l l brown a r e a s a t base and apex, and w i t h a brown s t r e a k e x t e n d i n g back from apex a l o n g the d o r s a l edge; t i b i a e s l i g h t l y t i n g e d w i t h brown a t base. No d i s t i n c t m a c u l a t i o n on s t e r n i t e s , e x c e p t a p a l e l a t e r a l edge and a n t e r i o r w h i t e d o t s on each s t e r n i t e . G i l l s w i t h an i n t e r i o r dark band c l o s e t o d o r s a l margin and a t h i c k -ened v e n t r a l m a r g i n . T r a c h e a t i o n d i s t i n c t but not p r o m i n e n t . T a i l s p a l e , w h i t i s h , v e r y b r o a d l y banded w i t h brown i n m i d d l e and a p i c a l l y . D i s t r i b u t i o n : B r i t i s h C olumbia -32-No specimens o f t h i s s p e c i e s were examined. AMELETUS COOK I McDUNNOUGH Ameletus C o o k i McDunnough, Needham, 1935, The B i o l o g y o f M a y f l i e s , 452 ( B i b l i o g r a p h y ) A d u l t : S m a l l dark s p e c i e s , w i t h orange-brown abdominal t e r g i t e s ; t h o r a x b l a c k i s h - b r o w n , w i t h orange s h a d i n g on and b e f o r e mesothor* a c i c s c u t e l l u m , a t wing and l e g bases; wings h y a l i n e , l o n g i t u d i n a l v e i n s amber; abdominal t e r g i t e s orange-brown, w i t h s u f f u s e d brown s h a d i n g a l o n g l a t e r a l m a r g i n s , f o r m i n g o b s c u r e s e m i - t r i a n g u l a r p a t c h e s i n the p o s t e r o - l a t e r a l c o r n e r s , sometimes e x t e n d i n g narrow a l o n g the p o s t e r i o r m a r g i n . S t e r n i t e s 2-6 d u l l h y a l i n e w h i t i s h , 7 and 8 opaque, b r i g h t y e l l o w i s h , 9 b l a c k i s h brown shaded w i t h o range; g a n g l i o n i c m a r k i n g s orange; penes each b e a r i n g a s p i n e on i n n e r margin near m i d d l e ; penes c u r v e d a t t i p ; t a i l s d i r t y w h i t i s h j o i n i n g s d a r k . Nymph: Femur w i t h a brown c e n t r a l p a t c h on o u t e r s i d e , which may be red u c e d ; t i b i a e brown a t base; s t e r n i t e s p a l e , s t e r n i t e s 3-7 each w i t h a p a i r of s m a l l brown submedian s p o t s near a n t e r i o r margin and a l a t e r a l brown s t r e a k , which i s f a i n t on segments 6 and 7; s t e r n i t e s 8 and 9 a r e each c r o s s e d by a broad c u r v e d brown band, l e a v i n g o n l y the a n t e r o - l a t e r a l and p o s t e r o - m e d i a l a r e a s p a l e ; g i l l s each w i t h a t h i n b l a c k c h i t i n o u s band near d o r s a l m a r g i n ; t a i l s p a l e w i t h a broad deep brown median band. D i s t r i b u t i o n : Montana, B r i t i s h C o l u m b i a . No specimens o f t h i s s p e c i e s were examined. -33-AfflELETUS filONTA MAYO Ameletus monta Mayo, Hflayo, 1952, Pan.Pac.Ent.,' 28:93 ( b i b l i o g r a p h y ) A d u l t : ( M a l e ) UJings w i t h a r e d d i s h - b r o w n t i n g e due t o prominence o f re d d i s h - b r o w n l o n g i t u d i n a l v e i n s ; c r o s s v e i n s l e s s d i s t i n c t ; s t i g m a t i c a r e a m i l k y ; f i r s t abdominal t e r g i t e dark brown, t e r g i t e s 2-7 s e m i - h y a l i n e , washed w i t h p a l e t r a c h e a t i o n s and very p a l e l a t e r a l l y , t e r g i t e s 8-10 dark brown w i t h a p a l e s t r e a k on the edges; s t e r n i t e s 2-8 w i t h b l a c k i s h g a n g l i o n i c m a r k i n g s ; penes narrow, p a r a l l e l , s l i g h t l y i n c u r v e d a t t i p s , each w i t h 3 prominent s p i n e s a t base; t a i l s w h i t e w i t h minute brown h a i r s , each segment d e l i c a t e l y b o r d e r e d p o s t e r i o r l y w i t h r e d d i s h h a i r . Nymph: Legs y e l l o w i s h brown, w i t h l a s t t a r s a l segment dark r e d d i s h brown; abdominal s t e r n i t e 1 p a l e , 2-4 and 8 u n i f o r m l y p a l e , 5-7 p a l e e x c e p t around g a n g l i o n i c m a r k i n g s ; 9 p a l e ; each s t e r n i t e w i t h brown p a t c h e s on e i t h e r s i d e o f m i d l i n e , and s m a l l d i s t i n c t w h i t e p a t c h e s on a n t e r o - l a t e r a l c o r n e r s ; t r a c h e a e o f g i l l s numerous; s c l e r o t i z e d band on g i l l s as f a r from d o r s a l margin as w i d t h o f base; t a i l s f r i n g e d , p a l e w i t h dark brown median band. D i s t r i b u t i o n : B r i t i s h Columbia No specimens of t h i s s p e c i e s were examined. AMELETUS OREGQNENSIS McDUNNOUGH Ameletus o r e q o n e n s i s fflcDunnough, McDunnough, 1936, Can.Ent., 68:208 ( B i b l i o g r a p h y ) -34-A d u l t : Head and t h o r a x b l a c k i s h , abdomen y e l l o w i s h w h i t e ; wings h y a l i n e , c o s t a l a r e a f a i n t l y a m b e r - t i n g e d a t base; b a s a l a n a l a r e a 1 and s t i g m a t i c r e g i o n of f o r e w i n g s u f f u s e d w i t h s e p i a brown; the b a s a l a r e a o f the h i n d w i n g , e x t e n d i n g a l o n g c o s t a h a l f way t o apex, i s p r e d o m i n a n t l y brown; \/enation brown; c r o s s v e i n s numerous, anastomosed i n stigma;;;,-\" a b d o m i n a l t e r g i t e s 2 smoky brown, 3-6 s e m i -h y a l i n e , p a l e y e l l o w i s h w h i t e w i t h p o s t e r i o r m a r g i n s , t r i a n g l e s i n the p o s t e r o - l a t e r a l c o r n e r s , and two narrow s u b m e d i a h s t r e a k s dark brown, 7-9 opaque, m a r k i n g s the same but b l a c k i s h brown, 10 brown w i t h p a l e p o s t e r i o r m a r g i n ; s t e r n i t e s 1-6 s e m i - h y a l i n e , p a l e y e l l o w i s h w h i t e , 7-9 opaque, s u f f u s e d w i t h brown; no g a n g l i o n i c m a r k i n g s ; penes u n i q u e , each composed of a wide c h i t i n o u s p i e c e b e a r i n g t h r e e b road s p i n e s a t i t s apex; penes s h o r t , not r e a c h i n g the apex of t h e f o r c e p s base; t a i l s p a l e smoky, not darkened a t j o i n i n g s . Nymph: B a s a l a r e a o f femur p a l e w i t h a deep broad brown median band; a p i c a l s e c t i o n more or l e s s l i g h t e r brown, e s p e c i a l l y i n the f o r e femur; b a s a l h a l v e s of t i b i a e p a l e , a p i c a l h a l v e s brown; abdominal s t e r n i t e s u n i f o r m l y p a l e brown, w i t h no g a n g l i o n i c m a r k i n g s ; g i l l s p a l e , w i t h poor t r a c h e a t i o n ; a dark brown i n t e r i o r band of c h i t i n i n the g i l l s and w i t h v e n t r a l margins b r o a d l y but i n d i s t i n c t l y t h i c k e n e d w i t h c h i t i n ; t a i l s brown a t base and then banded a l t e r n a t e l y p a l e and dark brown, t i p s w h i t i s h . -35-D i s t r i b u t i o n : Oregon, B r i t i s h C o l u m b i a . No specimens o f t h i s s p e c i e s were examined. AIY1ELETUS QUERULU5 McDUNNOUGH Ameletus q u e r u l u s fflcDunnough, fflcDunnough, 1938, Can. E n t . , 70:29 ( B i b l i o g r a p h y ) A d u l t : ( f f l a l e ) UJings p a l e h y a l i n e w i t h l o n g i t u d i n a l v e i n s and c r o s s v e i n s i n p t e r o s t i g m a t i c a r e a brown; abdominal t e r g i t e s 2-6 s e m i - h y a l i n e , l i g h t y e l l o w - b r o w n s h a d i n g i n t o deeper brown a l o n g t h e p o s t e r i o r b o r d e r s , and r a t h e r s t r o n g l y marked w i t h a f i n e dark t r a c h a a t i o n a r i s i n g from the dark l a t e r a l band, t e r g i t e s 7-10 opaque, s l i g h t l y deeper i n c o l o u r t h a n a n t e r i o r t e r g i t e s and w i t h some l a t e r a l d a r k e r s h a d i n g ; s t e r n i t e s w h i t i s h , s u f f u s e d w i t h d u l l smoky; no g a n g l i o n i c m a r k i n g s . Nymph: Femora p a l e , t i p p e d w i t h dark and each w i t h s m a l l median o v a l dark s p o t ; abdominal s t e r n i t e s 1-7 p a l e , 8-9 d a r k ; s t e r n i t e s 1 and 2 each bear 2 dark submedian s p o t s , much l a r g e r on 2; on s t e r n i t e s 3-6 t h e s e s p o t s become p r o g r e s s i v e l y l a r g e r , u n i t i n g w i t h dark s h a d i n g on the a n t e r i o r margins to form l a r g e i r r e g u l a r l y t r i a n g u l a r p a t c h e s , o c c u p y i n g the whole median a r e a , a p i c e s t o u c h i n g the p o s t e r i o r m a r g i n s ; f a i n t l a t e r a l dark p a t c h e s on s t e r n i t e s 3-4 a l s o become p r o g r e s s i v e l y l a r g e r and on 5 c o n n e c t w i t h the dark median a r e a ; no l a t e r a l p a t c h e s on s t e r n i t e 6 ; on s t e r n i t e 7 the t r i a n g u l a r a r e a i s r e v e r s e d ; g i l l s o v a l w i t h the dark c h i t i n o u s band w e l l w i t h i n the d o r s a l margin and e x t e n d i n g o n l y 2/3 t o the t i p of t h e g i l l ; 36-t a i l s p a l e w i t h a m o d e r a t e l y uiide dark median band. D i s t r i b u t i o n : B r i t i s h C olumbia No specimens of t h i s s p e c i e s were examined. AMELETUS SIMILIQR McDUNNOUGH Ameletus s i m i l i o r McDunnough, Needham, 1935, The B i o l o g y o f May-f l i e s , 456 ( B i b l i o g r a p h y ) A d u l t : Medium s i z e d dark s p e c i e s ; head and t h o r a x s h i n y b l a c k i s h brown i n male; t h o r a x b r i g h t r e d d i s h brown i n f e m a l e ; wings h y a l i n e , c l o u d s of l i g h t umber brown i n male; v e n a t i o n d a r k , s e v e r a l c r o s s -v e i n s of f o r e w i n g margined w i t h brown, so wing appears s p e c k l e d ; a b dominal t e r g i t e s deep brown w i t h l i g h t e r s h a d i n g on p o s t e r i o r m a r g i n s ; s t e r n i t e s w i t h b l a c k , h e a r t - s h a p e d g a n g l i o n i c m a r k i n g s ; t u b e r c l e s on f o r c e p s base p o o r l y d e v e l o p e d ; penes s l i g h t l y i n c u r v e d a t t i p s , each bears one o r more s p i n e s on i n n e r m a r g i n ; s u b a n a l p l a t e o f female s m a l l , c o v e r i n g l e s s t h a n one h a l f the t e n t h segment. Nymph: Femora each w i t h a p a l e s t r e a k e x t e n d i n g backward from d i s t a l e x t r e m i t y ; t a r s i w i t h dark brown a p i c a l bands; s t e r n i t e s 3, 4, and 8 dark brown, o t h e r s p a l e w i t h f a i n t dark l a t e r a l dashes and o b s c u r e submedian s t r e a k s u n i t i n g a t t i m e s , e s p e c i a l l y on s t e r n i t e 8, t o form p a t c h e s ; s t e r n i t e 9 e n t i r e l y p a l e w i t h a minute dark dot i n each a n t e r o - l a t e r a l c o r n e r ; g a n g l i o n i c markings d i s t i n c t and b l a c k i s h ; g i l l s n a r r o w l y o v a l , f e e b l y t r a c h e a t e d , and w i t h a c h i t i n o u s t h i c k -e n i n g a l o n g t h e d o r s a l . a n d v e n t r a l edges; t a i l s p a l e , w i t h a b r o a d deep brown median band. -37-D i s t r i b u t i o n : A l b e r t a , B r i t i s h C olumbia No specimens o f t h i s s p e c i e s mere examined. AMELETUS SPARSATU5 lYIcDUNNOUGH Ameletus s p a r s a t u s McDunnough, Needham, 1935, The B i o l o g y o f May-f l i e s , 456 ( B i b l i o g r a p h y ) A d u l t : Head, pronotum and metanotum b l a c k , a n t e r i o r p a r t of l a t t e r shaded w i t h brown; mesonotum r e d d i s h brown a n t e r i o r l y , y e l l o w i s h brown m e d i a l l y and b l a c k i s h brown l a t e r a l l y ; s c u t e l l u m y e l l o w i s h brown w i t h b l a c k l a t e r a l m a r g i n s ; wings h y a l i n e , a m b e r - t i n t e d i n male; v e n a t i o n brown; c r o s s v e i n s i n c o s t a l h a l f o f f o r e w i n g basad o f the b u l l a margined w i t h brown, so t h a t wing appears s p e c k l e d ; c r o s s v e i n s i n s t i g m a t i c a r e a s t r o n g l y anastomosed; abdominal t e r g i t e s 2-6 y e l l o w i s h brown, r e s t g o l d e n brown; a l l t e r g i t e s b r o a d l y shaded w i t h d a r k e r brown on l a t e r a l and p o s t e r i o r m a r g i n s ; s t e r n i t e s 2-6 d u l l smoky brown, r e s t opaque y e l l o w i s h brown, w i t h dark a n t e r o -median p a t c h e s on.7 and 8, and a b r o a d deep brown l a t e r a l edging on 9; penss as i n A^ c o o k i . Nymph: Legs banded; abdominal t e r g i t e s 1, 7 and 10 p a l e w i t h a dark a n t e r i o r m a r g i n ; t e r g i t e 9 and s t e r n i t e s 8 and 9 dark r e d d i s h t o orange brown; o t h e r t e r g i t e s w i t h p a l e l a r g e o v a l l a t e r a l s p o t s , p a l e median a r e a s bounded by dark brown submedian o b l i q u e s t r e a k s , a n t e r i o r and p o s t e r i o r margins v e r y n a r r o w l y b l a c k , e s p e c i a l l y i n -38-p o s t e r o - l a t e r a l c o r n e r s ; s t e r n i t e s s i m i l a r , w i t h o u t p a l e median s t r e a k ; t a i l s p a l e , w i t h wide median b l a c k band and narrow a p i c a l b l a c k band; no c h i t i n o u s band i n g i l l s ; t r a c h e a t i o n of g i l l s p l e n t i f u l and d i s t i n c t . D i s t r i b u t i o n : B r i t i s h C olumbia No specimens o f t h i s s p e c i e s were examined. AfflELETUS SUFFUSUS fflcDUNNOUGH Ameletus s u f f u s u s McDunnough, rflcDunnough, 1936, Can.Ent., 68:210 ( B i b l i o g r a p h y ) A d u l t : (IKlale) UJings t i n g e d w i t h umber-brown, p a l i n g somewhat o u t w a r d l y ; l o n g i t u d i n a l v e i n s b r i g h t brown, c r o s s v e i n s smoky brown, tho s e b e f o r e the b u l l a numerous and t h o s e i n the p t e r o s t i g m a t i c a r e a e v e n l y anastomosed; abdominal t e r g i t e 1 b l a c k i s h , o t h e r s r a t h e r b r i g h t y e l l o w , b r o a d l y b o r d e r e d w i t h brown p o s t e r i o r l y and s l i g h t l y brown-shaded a l o n g l a t e r a l edges where t r a c h e a t i o n shows as a f i n e dark network; t e r g i t e s 8-10 are opaque w i t h a more extended brown s u f f u s i o n ; s t e r n i t e s d u l l p a l e o c h r e o u s ; s t e r n i t e 9 and f o r c e p s p l a t e t i n g e d w i t h y e l l o w c e n t r a l l y ; no g a n g l i o n i c m a r k i n g s ; penes l o b e s wide a p a r t w i t h a p i c e s d i r e c t e d o u t w a r d l y ; t a i l s smoky, f a i n t l y dark r i n g e d . Nymph: Legs p a l e w i t h a dark c e n t r a l p a t c h on each femur; t a r s i banded b a s a l l y and a p i c a l l y w i t h brown; f i r s t 7 abdominal s t e r n i t e s w i t h a broad dark broken m e d i a l band, t a p e r i n g a n t e r i o r l y on each to a p o i n t and not q u i t e a t t a i n i n g t h e a n t e r i o r m a r g i n , and b r o a d e n i n g p o s t e r i o r l y , e s p e c i a l l y i n s t e r n i t e s 5 and 6 where i t a l m o s t c o e l e s c e s w i t h a dark l a t e r a l s t r i p e which i s s l i g h t l y m e d i a l t o t h e p a l e edge; s t e r n i t e s 8 and 9 brown w i t h s m a l l w h i t e s p o t s on t h e a n t e r i o r m a r g i n s ; g i l l s p a l e , t r a c h e a t i o n i n d i s t i n c t , d o r s a l edge s t r o n g l y c h i t i n i z e d ; t a i l s p a l e b r o w n i s h a t base and w h i t i s h a p i c a l l y , w i t h a broad deep brown median band and t i p s . D i s t r i b u t i o n ; B r i t i s h C olumbia No specimens of t h i s s p e c i e s were examined. AfflELETUS TUBERCULATUS McDUNNOUGH Ameletus t u b e r c u l a t u s fflcDunnough, fflcDunnough, 1939, Can. E n t . , 71:50 ( b i b l i o g r a p h y ) A d u l t : Wings h y a l i n e ; l o n g i t u d i n a l v e i n s brown, c r o s s v e i n s f i n e , i n c o n s p i c u o u s , and f a i n t l y shaded w i t h d a r k e r c o l o u r ; abdominal t e r g i t e s w i t h a n t e r i o r 2/3 s e m i - h y a l i n e , l i g h t smoky, s t r o n g l y v e i n e d w i t h d a r k e r , p o s t e r i o r l / 3 deep brown; two submedian dark l i n e s do not r e a c h a n t e r i o r m a r g i n s ; s t e r n i t e s p a l e d i r t y w h i t e w i t h a median row o f b l a c k g a n g l i o n i c m a r k i n g s ; male g e n i t a l i a s i m i l a r to A. c o n n e c t i n a but penes s h o r t e r and a c h a r a c t e r i s t i c l a r g e t u b e r c l e between, bases.' Nymph: Unknown D i s t r i b u t i o n : B r i t i s h Columbia No specimens o f t h i s s p e c i e s were examined. -40^ AMELETUS UALIDUS McDUNNOUGH Ameletus v a l i d u s McDunnough, Needham, 1935, The B i o l o g y o f M a y f l i e s , 458 ( B i b l i o g r a p h y ) A d u l t : Head and t h o r a x brown, abdomen p i n k i s h brown; wings h y a l i n e , f a i n t l y c l o u d e d w i t h p a l e umber brown i n male, v e n a t i o n d ark; s e v e r a l c r o s s v e i n s i n f o r e w i n g margined w i t h brown so t h a t wing appears s p e c k l e d ; a bdominal t e r g i t e s 1-5 semi t r a n s p a r e n t , s u t u r e s n a r r o w l y opaque; 7-10 opaque, 9 shaded l a t e r a l l y w i t h smoky brown; no g a n g l i o n i c m a r k i n g s ; penes c u r v e outward a t t i p s ; s u b a n a l p l a t e o f f e m a l e a l m o s t a t t a i n i n g p o s t e r i o r margin of t e n t h segment. Nymph: F i n e brown bands a t bases of femora and t i b i a e ; f i r s t and second femora each w i t h an o v a l brown s p o t on o u t e r s i d e , near m i d d l e ; s t e r n i t e s p a l e , w i t h f a i n t brown s t r e a k s a l o n g l a t e r a l edges of s t e r n i t e 9; g i l l s l a r g e , o v a l , p a l e , f a i n t l y t r a c h e a t e d , and w i t h t h i n dark c h i t i n o u s bands w e l l w i t h i n the d o r s a l m a r g i n s ; o u t e r t a i l s l i g h t brown, m i d d l e t a i l p a l e r and w i t h a f a i n t brown narrow median band. D i s t r i b u t i o n : A l b e r t a , B r i t i s h Columbia No specimens o f t h i s s p e c i e s were examined. AMELETUS UANCOUVERENSIS McDUNNOUGH Ameletus v a n c o u v e r e n s i s McDunnough, Needham, 1935, The B i o l o g y o f M a y f l i e s , 458 ( B i b l i o g r a p h y ) A d u l t : Deep mahogany brown s p e c i e s ; w i t h a l i g h t y e l l o w i s h brown -41-U-shaped mark on mesonotum, the base of the U on the s c u t e l l u m ; mings s t r o n g l y and e n t i r e l y t i n g e d o i i t h umber brown, s t i g m a t i c a r e a deeper; v e n a t i o n dark brown, c r o s s v e i n s numerous, th o s e i n s t i g m a anastomosed; abdominal t e r g i t e 1 mahogany brown, 2-7 s e m i - h y a l i n e , s h i n y b r i g h t y e l l o w i s h brown, shadi n g to n a r r o w l y dark brown p o s t e r i o r m a r g i n s , 8-10 opaque, mahogany brown, t i n g e d a n t e r i o r l y w i t h y e l l o w i s h brown; s t e r n i t e s 2-8 l i g h t o c h r e c u s , t i n g e d a n t e r i o r l y w i t h y e l l o w i s h brown, 9 b r i g h t y e l l o w i s h brown, dark brown a n t e r i o r l y and l a t e r a l l y ; no dark g a n g l i o n i c m a r k i n g s ; penes w i t h two l o n g sharp s p i n e s between the l a t e r a l p o r t i o n s ; t a i l s deep smoky, j o i n i n g s d a r k . Nymph; Unknown D i s t r i b u t i o n ; B r i t i s h C olumbia No specimens of t h i s s p e c i e s were examined. AIY1ELETUS VERNALIS (YlcDUNNOUGH Ameletus v e r n a l i s McDunnough, McDunnough, 1936, Can. E n t . , 68:208, ( B i b l i o g r a p h y ) A d u l t : Large s p e c i e s w i t h deep b l a c k i s h brown head and t h o r a x ; wings h y a l i n e , f o r e w i n g s shaded w i t h brown a t apex and w i t h a s l i g h t brown t i n g e a t the base of R3, where t h e r e i s a group of 6 c r o s s -v e i n s ; v e n a t i o n brown, e x c e p t 3 or 4 c o s t a l c r o s s v e i n s beyond the b u l l a which are p a l e and i n d i s t i n c t ; s t i g m a t i c c r o s s v e i n s anastomosed to form a s e r i e s of s m a l l e r c o s t a l c e l l s w i t h l a r g e r ones below; abdominal t e r g i t e s 2-6 t r a n s l u c e n t d u l l ' , g r e y i s h w h i t e , 7-10 opaque y e l l o w i s h , a l t h o u g h 9 i s brown; t e r g i t e s each w i t h a deep p u r p l e --42-brown s u b t r i a n g u l a r p a t c h , based on p o s t e r i o r m a r g i n , apex a l m o s t a t t a i n i n g a n t e r i o r m a r g i n , and brown l a t e r a l p a t c h e s ; s t e r n i t e s 2-6 w i t h f a i n t t r a c e s of m i d - v e n t r a l brown s p o t s c o n n e c t e d by a f i n e l i n e , 7 and B w i t h brown l a t e r a l p a t c h e s based on p o s t e r i o r m a r g i n s , 9 brown, y e l l o w i s h on p o s t e r i o r m a r g i n ; v/enter of female l a r g e l y t i n g e d w i t h p u r p l i s h brown; each penes w i t h a l o n g s p i n e on i n n e r s i d e . Nymph; Legs p a l e , femora w i t h l a r g e brown median p a t c h e s on o u t e r s i d e ; t i b i a e e n t i r e l y p a l e , e x c e p t at extreme base; s t e r n i t e s p a l e brown w i t h b r o a d l y p a l e l a t e r a l edges, e x c e p t i n s t e r n i t e 9 , and s m a l l p a l e d o t s near a n t e r o - l a t e r a l c o r n e r s ; g i l l s p a l e w i t h f a i n t t r a c h e a t i o n and an i n t e r i o r dark c h i t i n o u s band j u s t w i t h i n d o r s a l margin and f a i n t t r a c e s of c h i t i n o u s t h i c k e n i n g a l o n g the v e n t r a l edge; t a i l s p a l e w h i t i s h , b r o a d l y banded w i t h brown j u s t beyond m i d d l e and a t extreme t i p s . D i s t r i b u t i o n ; B r i t i s h C o l umbia No specimens of t h i s s p e c i e s were examined. APflELETUS SP. 1 Ameletus sp. 1 A d u l t ; Head dark brown, mesonotum y e l l o w i s h r e d , d a r k e r on each ^ s i d e of s c u t e l l u m ; metanotum d a r k e r ; wings amber t i n g e d , no ^ margined c r o s s v e i n s ; f o r e l e g s dark r e d d i s h brown, m i d d l e and h i n d l e g s y e l l o w - r e d ; abdominal t e r g i t e s 1 and 10 dark brown, 2-9 y e l l o w --43-r e d , d a r k e r on p o s t e r i o r m a r g i n s ; s t e r n i t e s 1 dark brown, 2-8 y e l l o w , 9 and 10 r e d d i s h brown; no dark g a n g l i o n i c m a r k i n g s . Nymph; Unknown. D i s t r i b u t i o n : B r i t i s h C olumbia M a t e r i a l Examined: 1 Male, 1 Female, B r i t i s h C o l u m b i a : C o u r t e r l a y , V I 1 1 . 3 . 3 1 , {3. S p e n c e r ) . GENUS PARAMELETUS BENGTSSON P a r a m e l e t u s , Needham, 1935, The B i o l o g y of M a y f l i e s , 502 ( B i b l i o g r a p h y ) Adult:'' Medium s i z e d b r o w n i s h m a y f l i e s , male and female ve r y s i m i l a r ; eyes o f male l a r g e , c o n t i g u o u s a p i c a l l y , n ot d i v i d e d ; f o r e l e g of male as long- as body; f i r s t j o i n t of f o r e - t a r s u s and f o r e - t i b i a t h i c k l y s e t with, b l u n t s p i n e - l i k e p r o c e s s e s , s p i n e s a t t i p s o f t a r s a l j o i n t s o f m i d d l e and h i n d l e g s ; h i n d t a r s u s s u b e q u a l to t i b i a ; c l a w s on t a r s i s i m i l a r , s h a r p - p o i n t e d ; p o s t e r i o r branch ofM of f o r e w i n g forms a l m o s t a r i g h t - a n g l e a t i t s u n i o n w i t h the stem; h i n d wing l e s s than t w i c e as l o n g as wide, median v e i n s i m p l e , not f o r k e d ; c o s t a l a n g u l a t i o n o b t u s e ; abdominal t e r g i t e s 5-9 not d i l a t e d l a t e r a l l y i n t o f l a t , b r oad \u00E2\u0080\u00A2 extensions'; f o r c e p s base s h a l l o w l y e x c a v a t e d on i t s a p i c a l m a r g i n , v e r y b l u n t p r o j e c t i o n s on each s i d e o f t h i s e x c a v a t i o n ; a s h o r t 5 - j o i n t e d r udiment of the m i d d l e t a i l r e m a i n s . Genotype: P a r a m e l e t u s c h e l i f e r Bengtsson -44-PARAMELETUS CDLU1YIBIAE McDUNNOUGH Pa r a m e l e t u s c o l u m b i a e McDunnouqh. McDunnough, 1938, Can. E n t . , 70: 23-34 ( B i b l i o g r a p h y ) A d u l t : (lYlale) . Wings h y a l i n e w i t h deep brown v e n a t i o n ; abdominal t e r g i t e s deep brown, p a l i n g a l o n g a n t e r i o r b o r d e r s of 1-6, 7-10 opaque, shaded w i t h l i g h t e r brown, e s p e c i a l l y l a t e r a l l y ; s t e r n i t e s the same, but r u d d i e r , , and p o s t e r i o r margins of a n t e r i o r segments b o r d e r e d n a r r o w l y w i t h d i r t y w h i t e ; b a s a l p l a t e d u l l o c h r e o u s , w i t h a U-shaped ruddy work; t a i l s smoky, p a l e r a t j o i n t s . Nymph: Unknown D i s t r i b u t i o n : B r i t i s h Columbia No specimens of t h i s s p e c i e s were examined. GENUS SIPHLONURUS EATON Siphlonurus,Needham, 1935, The B i o l o g y of M a y f l i e s , 460 ( B i b l i o g r a p h y ) A d u l t : Male and female s i m i l a r , a p p e a r i n g a n n u l a t e o f t e n ; eyes o f male l a r g e , u s u a l l y c o n t i g u o u s a p i c a l l y , not d i v i d e d . Eyes of both s e x e s w i t h a t r a n s v e r s e band, of d i f f e r e n t c o l o u r than the eye, o b l i q u e l y a c r o s s eye; f o r e l e g of male as l o n g or s l i g h t l y l o n g e r than body; f i r s t f o r e t a r s a l j o i n t of male 3/4 t o 7/8 o f o r s u b e q u a l to second; f i r s t and second j o i n t s of f o r e t a r s u s w i t h b l u n t s p i n e -l i k e p r o c e s s e s on m a r g i n s ; sharp s p i n e s on margin o f f o r e t i b i a , and margins and t i p s of m i d d l e and h i n d t a r s i ; c l a w s s i m i l a r , s h a r p -p o i n t e d ; h i n d t a r s u s l o n g e r than h i n d t i b i a ; f o r e w i n g l o n g and narrow, -45-t h r e e t i m e s as l o n g as w i d e ; h i n d wing l e s s t h a n t w i c e as l o n g as wide; v e n a t i o n d a r k ; hemeral c r o s s v e i n s t r o n g and d a r k ; s t i g m a t i c c r o s s v e i n s f r e q u e n t l y anastomosed; c o s t a l a n g u l a t i o n of h i n d wing m e r e l y a rounded e l e v a t i o n ; median v e i n f o r k e d about l/3 t h e d i s t a n c e from the base t o the o u t e r m a r g i n ; abdominal t e r g i t e s w i t h dark t r i a n g l e s w i t h bases on p o s t e r i o r m a r g i n s , and a p i c e s not q u i t e a t t a i n i n g a n t e r i o r m a r g i n s , a l s o dark o v a l submedian s p o t s on a n t e r i o r margins i n a n t e r i o r segments, but near c e n t e r i n a p i c a l segments; s t e r n i t e s w i t h dark U-shaped marks, l a t e r a l dark t r i a n g l e s which may o r may not be u n i t e d a t b a s e s , or a c o n t i n u o u s o r d i s -c o n t i n u o u s dark median l i n e , w i t h one o r two p a i r s of s m a l l d o t s near i t ; f o r c e p s base very l o n g , s l i g h t l y concave i n i t s a p i c a l m a r g i n ; b a s a l j o i n t o f f o r c e p s an i m p e r f e c t l y s e p a r a t e d r i n g - l i k e e n largement o f the l o n g j o i n t ; two d i s t a l j o i n t s t o g e t h e r not l o n g e r t h a n the l o n g j o i n t ; the i n n e r a p i c a l margin of the b a s a l j o i n t o f t e n extended l a t e r a l l y beyond the base of the l o n g j o i n t ; penes complex, c o n s i s t i n g u s u a l l y of p a i r e d v e n t r a l and d o r s a l c h i t i n i z e d p o r t i o n s , of which one p a i r c o m p l e t e l y o v e r l i e s t h e o t h e r ; from b e n e a t h , the penes not u s u a l l y seen above the a p i c a l margin o f f o r c e p s base; s u b a n a l p l a t e of female b r o a d , convex i n i t s a p i c a l m a r g i n . Nymph: Compressed, s t r e a m l i n e d body; m a x i l l a r y and l a b i a l p a l p i 3 - j o i n t e d ; m a x i l l a c o n i c a l a t apex, w i t h a few s i m p l e h a i r s and s p i n e s on o u t e r and i n n e r m a r g i n s ; f r o n t a l margin of labrum e n t i r e and -46-s l i g h t l y concave; no s p i n e s on head or pronotum; clauis l o n g and s l e n d e r , not p e c t i n a t e , m e s o t h o r a c i c and m e t a t h o r a c i c c l a w s not l o n g e r than the p r o t h o r a c i c c l a w s ; w e l l - d e v e l o p e d p o s t e r o - l a t e r a l s p i n e s on the t h i n f l a t t e n e d l a t e r a l m a r gins o f the abdominal t e r g i t e s ; g i l l s l a r g e and p l a t e l i k e , r e t u s e on a p i c a l m a r g i n s ; t r a c h e a t i o n abundant; g i l l s double on segments 1 and 2 o r on segments 1-7; l a m e l l a e e q u a l i n s i z e , e x c e p t on segment 7. Genotype: S i p h l o n u r u s f l a v i d u s ( i n B a e t i s ) Ed. P i c t e t SIPHLONURUS Key To A d u l t s 1. Abdominal s t e r n i t e s l a r g e l y dark 2. Abdominal s t e r n i t e s l a r g e l y p a l e 3. 2. C o s t a l i n t e r c a l a r i e s j o i n i n g C u l t o h i n d margin of f o r e w i n g f o r k e d Isp. 1 C o s t a l i n t e r c a l a r i e s j o i n i n g C u l to h i n d margin of f o r e w i n g not f o r k e d . a u t u m n a l i s IYlcD 3. No U-shaped marks on abdominal s t e r n i t e s p . 2 U-shaped marks on abdominal s t e r n i t e s 4. 4. U-shaped marks on s t e r n i t e s 8-9 d i f f u s e d and p o o r l y d e f i n e d . P a l e ruddy s p o t on r e a r o f mesonotum .columbianus fflcD U-shaped marks c l e a r l y d e f i n e d on s t e r n i t e s 8-9. No ruddy s p o t on mesonotum... o c c i d e n t a l i s Eaton Key To Nymphs 1. Legs unbanded. UJide p a l e v e r t i c a l band between antennae b a s e s . G i l l s on segments 1-2 double 2. -47-Legs banded. No p a l e band between antennae b a s e s . G i l l s d o uble on segments 1-2 o r segments 1-7. .\u00E2\u0080\u00A2 4. 2. T a i l s p a l e , w i t h dark p r o x i m a l and m e d i a l t r a n s v e r s e bands. S m a l l U-shaped dark markings on s t e r n i t e s . A l l t e r g i t e s d a r k l y p a t t e r n e d sp. 4 T a i l s p a l e , w i t h a dark m e d i a l t r a n s v e r s e band. V e n t e r o f abdomen w i t h no dark m a r k i n g s . A l l t e r g i t e s not d a r k l y p a t t e r n e d .3. 3. T e r g i t e s 2, 3, 6, 7, and 9 p r e d o m i n a n t l y d a r k l y p a t t e r n e d , o t h e r s p a l e . G i l l t r a c h e a t i o n p a l e . . . . ...sp. 3 A l l t e r g i t e s w i t h a p a l e median t r i a n g u l a r and p a l e l a t e r a l m a r k i n g s . G i l l t r a c h e a t i o n dark \u00E2\u0080\u00A2 .sp. 5 4. G i l l s double on segments 1-2 o n l y o c c i d e n t a l i s Eaton G i l l s d o u b l e on segments 1-7. 5. 5. T a i l s unbanded. No p a t t e r n on t e r g i t e s or s t e r n i t e s sp. 6 T a i l s banded. T e r g i t e s or s t e r n i t e s p a t t e r n e d ....6. 6. T a i l s p a l e , w i t h a v e r y narrow dark m e d i a l band. L a t e r a l t r a n s v e r s e dark bands on a l l t e r g i t e s e x c e p t 5 and 8, which are, p a l e . S t e r n i t e s u n i c o l o u r e d . D o r s a l g i l l s p a t t e r n e d . .sp. 7 T a i l s not as above. A l l t e r g i t e s d ark. S t e r n i t e s p a t t e r n e d . G i l l t r a c h e a t i o n dark ...7. 7. T a i l s p a l e , w i t h p r o x i m a l , m e d i a l , and a p i c a l dark t r a n s v e r s e bands. S t e r n i t e s w i t h two s m a l l dark o b l i q u e l i n e s and two m e d i a l and two l a t e r a l dark s p o t s . M e d i a l dark l i n e on v e n t e r . . sp. 8 -48-T a i l s p a l e , w i t h m e d i a l and a p i c a l dark t r a n s v e r s e bands. S t e r n i t e s w i t h dark s u b m e d i a l e l o n g a t s . s p o t s . T e r g i t e s dark w i t h dark t r a n s v e r s e l a t e r a l bands s p . 9 Unknown S. a u t u m n a l i s McD S. c o l umbianus McD SIPHLONURUS AUTUMNALIS McDUNNOUGH S i p h l o n u r u s a u t u m n a l i s fflcDunnough, Needham, 1935, The B i o l o g y of M a y f l i e s , 467. ( B i b l i o g r a p h y ) A d u l t : A l a r g e dark s p e c i e s ; head and m e s o n o t a l s c u t e l l u m and sternum b l a c k i s h ; pronotum deep smoky; mesonotum dark .brown, p l e u r a l s u t u r e s p a l e y e l l o w i s h ; wings h y a l i n e ; v e n a t i o n deep brown; c o s t a l c r o s s -v e i n s i n b a s a l 2/3 of c o s t a l space weak; s t i g m a t i c c r o s s v e i n s heavy and s t r o n g l y anastomosed; abdominal t e r g i t e s deep p u r p l i s h brown; a n t e r i o r t r i a n g l e s t i n g e d w i t h y e l l o w ; l a t e r a l m a r g i n s , e s p e c i a l l y o f the f o u r a p i c a l segments, n a r r o w l y y e l l o w i s h ; s t e r n i t e s deep p u r p l i s h brown, p o s t e r i o r margins n a r r o w l y y e l l o w i s h ; p o s t e r o - m e d i a l a r e a o f s t e r n i t e 9 y e l l o w i s h ; a p i c a l margin of f o r c e p s base weakly e x c a v a t e d . Nymph: Unknown D i s t r i b u t i o n : A l b e r t a , B r i t i s h C olumbia M a t e r i a l Examined: 1 M a l e , B r i t i s h C o l u m b i a : B a r k e r v i l l e , V I I . 7 . 4 8 . (H.R. McCarthy) -49-SIPHLONURUS COLUiYiBIANUS McDUNNOUGH S i p h l o n u r u s c o l umbianus McDunnough. Needham, 1935, The B i o l o g y of M a y f l i e s , 469 ( B i b l i o g r a p h y ) A d u l t : A l a r g e dark s p e c i e s ; p a l e ruddy s p o t a n t e r i o r t o b l a c k m e s o t h o r a c i c s c u t e l l u m ; wings h y a l i n e ; f a i n t b r o w n i s h t i n g e i n s t i g m a t i c a r e a ; v e n a t i o n b l a c k i s h ; a bdominal t e r g i t e s deep p u r p l i s h brown, a n t e r i o r t e r g i t e s y e l l o w i s h ; s t e r n i t e s d u l l y e l l o w i s h ; U-shaped marks p u r p l i s h brown, d i f f u s e and p o o r l y d e f i n e d on s t e r n i t e s 8 and 9, s t e r n i t e 10 w h o l l y brown; two t i n y d o t s u s u a l l y near c e n t e r o f each s t e r n i t e ; t a i l s dark b a s a l l y , p a l e r d i s t a l l y ; j o i n i n g s brown. Nymph: Unknown D i s t r i b u t i o n : B r i t i s h C o l u m b i a , C a l i f o r n i a No specimens of t h i s s p e c i e s were examined. SIPHLONURUS OCCIDENTALIS EATON S i p h l o n u r u s o c c i d e n t a l i s E a t o n , Needham, 1935, The B i o l o g y o f M a y f l i e s , 473 ( B i b l i o g r a p h y ) A d u l t : A l a r g e r e d d i s h and y e l l o w i s h brown s p e c i e s ; head and t h o r a x y e l l o w i s h brown; pronotum dark brown,grey l a t e r a l l y ; m e s o n o t a l s c u t e l l u m and l a t e r a l m argins dark r e d d i s h brown, y e l l o w a r e a s a n t e r i o r t o m e s o n o t a l and m e t a n o t a l s c u t e l l a ; a n t e r o - l a t e r a l c o r n e r s o f mesonotum and p l e u r a l s u t u r e s y e l l o w i s h , o f t e n w i t h orange -50' m a r k i n g s ; w h i t e bands a c r o s s mesa and m e t a s t e r n a j wings h y a l i n e ; v e n a t i o n p u r p l i s h b l a c k ; l o n g i t u d i n a l v e i n s , h e a v i e r ; t h i c k e n e d a r e a s on b u l l a , Sc, R, and f i r s t d i v i s i o n o f Rs; narrow brown s h a d i n g a t base of f o r e w i n g , c o s t a l and s u b c o s t a l c r o s s v e i n s p a l e ; s t i g m a t i c c r o s s v e i n s numerous, o f t e n f o r k i n g near c o s t a l m a r g i n ; median p o r t i o n of each abdominal t e r g i t e y e l l o w i s h brown; l a t e r a l t r i a n g l e s d a r k , p r o m i n e n t , c o n f i n e d to p o s t e r o - l a t e r a l a n g l e s and l a t e r a l m a r g i n s ; dark o v a l s p o t s c o n s p i c u o u s and r e d d i s h brown; p a l e a r e a s s e m i -h y a l i n e ; a l l t e r g i t e s p a l e on p o s t e r i o r m a r g i n s ; a p i c a l t e r g i t e s marked w i t h y e l l o w , o f t e n w i t h powdery a r e a s ; U-marks on s t e r n i t e s c o n s p i c u o u s , the arms may be u n i t e d p o s t e r i o r l y by a brown c r e s c e n t i c or s t r a i g h t t r a n s v e r s e band; two s m a l l dark s p o t s w i t h i n each U-mark, a n t e r i o r t o c e n t e r ; t a i l s dark p u r p l i s h brown b a s a l l y , r e s t y e l l o w i s h o r w h i t i s h , j o i n i n g s s l i g h t l y d a r k e r . Nymph: Legs banded a l t e r n a t e l y l i g h t and dark; dark U-shaped markings on each abdominal s t e r n i t e ; g i l l s double on segments 1 and 2 o n l y ; t a i l s p a l e , dark banded a t t i p o n l y . D i s t r i b u t i o n : B r i t i s h C olumbia M a t e r i a l Examined: 1 ( ? ) B r i t i s h C o l u m b i a : Desmond, V I I I . 2 9 . 3 7 (O.K. Oacob) S i p h l o n u r u s sp.- 1 A d u l t : A v e r y l a r g e dark s p e c i e s ; head and t h o r a x dark brown; f o r e w i n g s - 5 1 -w i t h f o r k e d i n t e r c a l a r i e s j o i n i n g C u l t o h i n d m a r g i n ; abdominal t e r g i t e s and s t e r n i t e s b l a c k w i t h y e l l o w p o s t e r i o r m a r g i n s ; no U-shaped dark markings on s t e r n i t e s . Nymph: Unknown D i s t r i b u t i o n : B r i t i s h C o l umbia M a t e r i a l Examined: 1 Female, B r i t i s h C o l u m b i a : Cowichan, VI.20.49 (G.S. Brown) S i p h l o n u r u s sp. 2 A d u l t : UJings h y a l i n e , u n p a t t e r n e d ; abdominal t e r g i t e s 3-6 o n l y p a l e y e l l o w i s h brown, each w i t h two s u b m e d i a l t r i a n g l e s brown; t e r g i t e s 1-2 and 7-10 brown, p o s t e r i o r b o r d e r s b l a c k ; s t e r n i t e s 2-8 p a l e , w i t h dark g a n g l i o n i c m a r k i n g s , 9-10 dark brown; no U-shaped m a r k i n g s ; t a i l s p a l e , d a r k e r a t j o i n i n g s . Nymph: Unknown D i s t r i b u t i o n : B r i t i s h Columbia M a t e r i a l Examined: 1 M a l e , B r i t i s h C o l u m b i a : T r i n i t y V a l l e y * V I I . 2 . 4 3 (C.V. Morgan) S i p h l o n u r u s s p . 3 A d u l t : Unknown Nymph: A wide p a l e v e r t i c a l band between antennae b a s e s ; l e g s unbanded; abdominal t e r g i t e s 2, 3, 6, 7, and 9 p r e d o m i n a n t l y d a r k l y p a t t e r n e d , -52-o t h e r s p a l e ; g i l l s d ouble on segments 1 and 2 o n l y ; t r a c h e a t i o n p a l e ; no U-shaped markings on s t e r n i t e s ; t a i l s p a l e , w i t h a dark median t r a n s v e r s e band. E c o l o g y : Nymphs of t h i s s p e c i e s were t a k e n from t h e edge of t h e A l o u e t t e R i v e r a t a depth of 1 t o 2 f e e t . The c u r r e n t was s l o w and the r i v e r bed c o n s i s t e d o f a m i x t u r e o f c o a r s e and f i n e g r a v e l , sand, mud, and o r g a n i c s i l t and d e b r i s . A l l specimens were t a k e n d u r i n g mid-3une. D i s t r i b u t i o n : B r i t i s h C olumbia M a t e r i a l Examined: 7 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) y i . ? . 5 g (N. F i l m e r ) , Canim Lake, VI.27.61 (G.G.E. S c u d d e r ) . S i p h l o n u r u s s p . 4 A d u l t : Unknown Nymph: Wide p a l e band between antennae b a s e s , l e g s unbanded; a l l t e r g i t e s d a r k l y p a t t e r n e d ; U-shaped markings on s t e r n i t e s ; g i l l s d o u b l e on segments 1 and 2 o n l y ; t r a c h e a t i o n dark; t a i l s w i t h p r o x i m a l and median dark bands. D i s t r i b u t i o n : B r i t i s h C olumbia M a t e r i a l Examined: 2 Nymphs, B r i t i s h C o l u m b i a : Canim Lake, VI.27.61 (G.G.E. Sc u d d e r ) -53-' S i p h l o n u r u s s p . 5 A d u l t ; Unknown IMymph; UJide p a l e band between antennae bas e s ; l e g s unbanded; t e r g i t e s w i t h p a l e t r i a n g u l a r and l a t e r a l marks; no marks on s t e r n i t e s ; g i l l s double on segments 1 and 2 o n l y ; t r a c h e a t i o n dark; t a i l s w i t h dark median band. D i s t r i b u t i o n : B r i t i s h Columbia M a t e r i a l Examined: 1 Nymph, B r i t i s h C o l u m b i a : Canim Lake, VI.27.61 (G.G.E. Scudder) S i p h l o n u r u s s p . 6 A d u l t ; Unknown Nymph: Legs banded; no p a t t e r n on t e r g i t e s o r s t e r n i t e s ; g i l l s double on segments 1 t o 7; no t r a c h e a t i o n ; t a i l s unbanded. D i s t r i b u t i o n ; B r i t i s h C olumbia M a t e r i a l Examined: 6 Nymphs, B r i t i s h C o l u m b i a : N i c o l a Creek. S i p h l o n u r u s s p . 7 A d u l t ; Unknown Nymph: Legs banded; t e r g i t e s w i t h l a t e r a l t r a n s v e r s e dark bands; t e r g i t e s 5 and 8 p a l e ; s t e r n i t e s u n i c o l o u r e d , w i t h no p a t t e r n ; g i l l s double on segments 1 t o 7, d o r s a l g i l l s p a t t e r n e d ; t a i l s w i t h a v e r y narrow -54-dark m e d i a l band. D i s t r i b u t i o n : B r i t i s h C o l umbia m a t e r i a l Examined: 19 Nymphs, B r i t i s h C o l u m b i a : N i c o l a Creek. S i p h l o n u r u s s p . 3 A d u l t : Unknown ' Nymph: Legs banded; t e r g i t e s d a r k l y p a t t e r n e d ; s t e r n i t e s w i t h two s m a l l o b l i q u e l i n e s and two m e d i a l and two l a t e r a l dark s p o t s , s p o t s may be p a l e r ; dark m e d i a l l i n e on s t e r n i t e s ; g i l l s d o u b l e on segments 1 t o 7; t r a c h e a t i o n d a r k ; t a i l s w i t h p r o x i m a l , m e d i a l and a p i c a l dark bands. D i s t r i b u t i o n : B r i t i s h Columbia m a t e r i a l Examined: 4 Nymphs, B r i t i s h C o l u m b i a : n r . Rock Lake, VII.16.62 (G.G.E. ' S c u d d e r ) . S i p h l o n u r u s s p . 9 A d u l t : Unknown Nymph: Legs banded; abdominal t e r g i t e s dark w i t h d a r k e r l a t e r a l t r a n s v e r s e bands; s t e r n i t e s w i t h dark s u b m e d i a l e l o n g a t e s p o t s ; g i l l s double.on segments 1 t o 7; t r a c h e a t i o n d a r k ; t a i l s w i t h median and a p i c a l dark bands. -55-D i s t r i b u t i o n ; 8 r i t i s h C olumbia M a t e r i a l Examined: 6 Nymphs, B r i t i s h C o l u m b i a : 5 Brunson Lake, VI.25.61 (G.G.E. Scu d d e r ) 1 W i l l i a m s Lake, VI.24.61 (G.G.E. Scudder) SUBFAMILY HEETAGENIINAE A d u l t : Eyes o f males s i m p l e ; h i n d t a r s i w i t h f i v e f r e e l y movable j o i n t s ; wing v e n a t i o n p l e n t i f u l i n both w i n g s ; two p a r a l l e l p a i r s o f c u b i t a l i n t e r c a l a r i e s , u n a t t a c h e d b a s a l l y , i n f o r e w i n g , the p a i r n e a r e s t the h i n d a n g l e i s l o n g e r ; o u t e r f o r k of Rs o f h i n d wing p r e s e n t ; f o r c e p s 4 - j o i n t e d . Nymphs: F l a t t e n e d , p r o t e c t i v e l y c o l o u r e d nymphs; heads s t r o n g l y d e p r e s s e d ; eyes l a t e r a l ; labrum c o n s i d e r a b l y w i d e r t h a n l o n g ; m a n d i b l e s s l e n d e r i n b a s a l h a l f ; two c a n i n e s , the o u t e r l o n g e r t h a n the i n n e r ; c a n i n e s scoop-shaped, margins more o r l e s s c r e n a t e , may be one or two sharp s p i n e s on t i p of i n n e r c a n i n e ; l a c i n i a p r e s e n t or a b s e n t , i f a b s e n t , a row o f h a i r s o f t e n i n l a c i n i a l r e g i o n ; m a x i l l a r y p a l p i t w o - j o i n t e d , d i s t a l j o i n t o f t e n t h i c k l y s e t w i t h a p i c a l s p i n e s ; i n n e r m a r g i n of g a l e a - l a c i n i a w i t h a f r i n g e of l o n g h a i r s u s u a l l y a second row p a r a l l e l to t h e s e a s h o r t d i s t a n c e back from m a r g i n ; upper margin or crown of g a l e a - l a c i n i a w i t h s p i n e s o r h a i r s , o r b o t h ; l a b i a l p a l p i s i m i l a r to m a x i l l a r y p a l p i ; g i l l s p r e s e n t on abdominal segments 1-7; g i l l s d o u b l e , c o n s i s t i n g o f a d o r s a l l a m e l l a t e and a v e n t r a l f i b r i l l a n p o r t i o n , l a t t e r may be w a n t i n g , much r e d u c e d , o r pushed upwards t o appear t o l i e d o r s a l t o l a m e l l a t e p o r t i o n . . . -56-SUBFAmiLY HEPTAGENIINAE Key To A d u l t s 1. B a s a l j o i n t of f o r e t a r s u s o f male not as l o n g as second j o i n t 2. B a s a l j o i n t o f . f o r e t a r s u s of male e q u a l t o or s l i g h t l y l o n g e r than second j o i n t Epeorus Eaton 2. B a s a l j o i n t of f o r e t a r s u s o f male 2/3 t o 3/4 as l o n g as second j o i n t . 3. B a s a l j o i n t of f o r e t a r s u s of male l / 6 to l / 2 as l o n g as second j o i n t 4. 3. S t i g m a t i c a r e a o f ' f o r e w i n g d i v i d e d by a f i n e l i n e i n t b an upper and lower s e r i e s of c e l l u l e s . B a s a l c o s t a l c r o s s v e i n s v e r y weak Cinyqma Eaton\" S t i g m a t i c a r e a of f o r e w i n g not d i v i d e d by a f i n e l i n e i n t o an upper and' lower s e r i e s o f c e l l u l e s . B a s a l c o s t a l c r o s s v e i n s u s u a l l y w e l l - d e v e l o p e d . . . . . . Cinyqmula filcD 4. S t i g m a t i c c r o s s v e i n s more or l e s s anastomosed. Eyes of male u s u a l l y c o n t i g u o u s . . . R i t h r o q e n a Eaton S t i g m a t i c c r o s s v e i n s net anastomosed. Eyes of male not c o n t i g u o u s 5. 5. B a s a l j o i n t o f f o r e t a r s u s of male l / 6 to l / 3 as l o n g as the second j o i n t . Penes not d i s t i n c t l y L-shaped. S t i g m a t i c c r o s s -v e i n s not s l a n t e d H e p t a q e n i a Walsh B a s a l j o i n t o f f o r e t a r s u s o f male l / 3 to l / 2 as l o n g as the second j o i n t . Penes more or. l e s s d i s t i n c t l y L-shaped. S t i g m a t i c c r o s s v e i n s v a r i a b l y s l a n t e d .Stenonema T r a v e r -57-Key To Nymphs 1. Three t a i l s ,2. Two t a i l s Epeorus Eaton 2. G i l l s o f s e v e n t h p a i r o f g i l l s f l a t and p l a t e - l i k e , q u i t e s i m i l a r t o p r e c e d i n g p a i r s . Tracheae w i t h l a t e r a l branches always p r e s e n t i n s e v e n t h p a i r . E i t h e r s p i n e s or h a i r s on crown o f g a l e a - l a c i n i a , but not both 3. G i l l s of s e v e n t h p a i r of g i l l s r e d uced t o a s i n g l e s l e n d e r t a p e r e d f i l a m e n t on s p i n e . T r a c h e a e , i f p r e s e n t i n t h i s f i l a m e n t , w i t h o u t l a t e r a l b r a n c h e s . Both s p i n e s and h a i r s on crown o f g a l e a - l a c i n i a . .Stenonema T r a v e r 3. G i l l s o f f i r s t and second segments s m a l l e r t h a n r e s t , a l l g i l l s d i r e c t e d l a t e r a l l y , o r d o r s a l l y and l a t e r a l l y , n ot c o n v e r g i n g beneath body. F i b r i l l a r g i l l s v e n t r a l 4. G i l l s o f f i r s t and l a s t segments much e n l a r g e d , c o n v e r g i n g beneath body of nymph. F i b r i l l a r g i l l s d o r s a l R i t h r o q e n a Eaton 4. F i b r i l l a r p o r t i o n of g i l l s w e l l d e v e l o p e d on segments 1 to 6, may be wanting on segment. F r o n t o f h e a d e n t i r e o r v e r y s l i g h t l y e m a r g i n a t e . . 5. F i b r i l l a r p o r t i o n o f g i l l s r educed t o a few t i n y t h r e a d s . F r o n t o f head d i s t i n c t l y e m a r g i n a t e Cinyqmula fYlcD 5. A c h i t i n i z e d a r e a on each mandible below molar r e g i o n . I n n e r c a n i n e l / 2 as l o n g as o u t e r . H a i r s on crown o f g a l e a - l a c i n i a . L a t e r a l s p i n e s a b s e n t . Labrum e x t e n d i n g not more th a n l / 4 d i s t a n c e a l o n g a n t e r i o r margin of head Cinyqma Eaton -58-No c h i t i n z e d a r e a on m a n d i b l e . Inner c a n i n e a t l e a s t 3/4 as l o n g as o u t e r . S p i n e s on crouin o f g a l e a - l a c i n i a . Labrum e x t e n d i n g 2/3 t o 3/4 d i s t a n c e a l o n g a n t e r i o r margin of head H e p t a q e n i a Walsh GENUS CINYGfflA EATON Cinyqma, Needham, 1935, The B i o l o g y of M a y f l i e s , 365 ( B i b l i o g r a p h y ) A d u l t : Eyes of male not c o n t i g u o u s ; f o r e l e g of male as l o n g as body; femur s l i g h t l y s h o r t e r than t i b i a , w hich i s about l / 2 the l e n g t h o f the t a r s u s ; b a s a l f o r e t a r s a l j o i n t 2/3 t o 3/4 as l o n g as t h e second, which i s s u b e q u a l to t h i r d ; f o u r t h j o i n t about 3/4 as l o n g as the t h i r d ; f i f t h j o i n t l / 2 as l o n g as f i r s t ; i n h i n d t a r s u s b a s a l j o i n t s l i g h t l y l o n g e r t h a n second; f i f t h j o i n t s l i g h t l y l o n g e r than b a s a l j o i n t ; a l l c l a w s d i s s i m i l a r ; s t i g m a t i c a r e a of f o r e w i n g d i v i d e d by a f i n e l i n e i n t o a s e r i e s of s m a l l c o s t a l and l a r g e r s u b c o s t a l c e l l s ; b a s a l c o s t a l c r o s s v e i n s v e r y weak; s t i g m a t i c c r o s s -v e i n s s l a n t e d ; p o s t e r i o r branch of IYI i n f o r e w i n g forms a l m o s t a r i g h t a n g l e a t i t s u n i o n w i t h the a n t e r i o r b r a n c h ; o u t e r f o r k o f Rs o f h i n d wing p r e s e n t ; a p i c a l margin of f o r c e p s base not d e e p l y e x c a v a t e d ; f o r c e p s 4 - j o i n t e d , u n i t e d a l m o s t t o base; a p a i r o f s m a l l median s p i n e s on bases of penes, and a s m a l l e r s p i n e on each d i v i s i o n , below apex; p o s t e r i o r margin of s u b a n a l p l a t e i n female r e t u s e . Nymph: F r o n t o f head e n t i r e o r s l i g h t l y e m a r g i n a t e ; labrum e x t e n d i n g not more than l / 4 the d i s t a n c e a l o n g the a n t e r i o r margin o f the head; mandible not v i s i b l e d o r s a l l y ; a c h i t i n i z e d a r e a basad of m o l a r a r e a of each m a n d i b l e ; i n n e r c a n i n e l / 2 as l o n g as o u t e r ; h a i r s on crown of g a l e a - l a c i n i a ; m a x i l l a r y p a l p i u s u a l l y not v i s i b l e d o r s a l l y ; g l o s s a e of l a b i u m d i s t i n c t l y t r i a n g u l a r ; , g i l l s on a l l segments d i r e c t l y l a t e r a l l y , 1 s t p a i r and 7 t h p a i r s m a l l e r than o t h e r s ; no f i n g e r l i k e p r o j e c t i o n s on g i i l l a m e l l a e ; f i b r i l l a r p o r t i o n o f g i l l s w e l l d e v e l o p e d on segments 1-6, may be w a n t i n g on segment 7, l o n g e r than l a m e l l a e on segment 1; a l l f i b r i l l a r p o r t i o n s v e n t r a l ; t h r e e t a i l s . Genotype; Cinyqma;. i n t e g r u m Eaton CINYG1Y1A INTEGRUM EATON Cinyqma i n t e g r u m E a t o n , S p i e t h , 1941, Ann. E n t . Soc. Amer., 34:88 ( B i b l i o g r a p h y ) A d u l t ; Reddish-brown s p e c i e s ; wings h y a l i n e , t i n g e d w i t h f a i n t g r e y i s h i n s t i g m a t i c a r e a and b a s a l a r e a ; v e n a t i o n dark brown; abdominal t e r g i t e s p a l e r h y a l i n e ; t e r g i t e 2 p u r p l i s h brown; t e r g i t e s 3-7 w i t h a median p u r p l e - b r o w n s t r i p e and a p a i r of subrnedial s t r i p e s , a p a l e c r e s e n t i c a r e a between t h e s e and the median s t r i p e ; s t e r n i t e w i t h p a l e p u r p l i s h brown t i n g e or l i g h t burnt-umber. Nymph: Unknown D i s t r i b u t i o n ; Oregon, B r i t i s h Columbia No specimens o f t h i s s p e c i e s were examined. -60-GENUS CINYGfflULA lYIcDUNNDUGH Ci n y q m u l a , Needha'm, 1935, The B i o l o g y o f m a y f l i e s , 384 ( B i b l i o g r a p h y ) A d u l t ; Eyes of male not c o n t i g u o u s , but s e p a r a t e d o n l y by a space l e s s t h a n l / 3 the s h o r t e r d i a m eter of the eye; f o r e l e g of male l o n g e r t h a n male; of f e m a l e , as l o n g as the body; f o r e femur of male 3/4 as l o n g as t i b i a ; which i s 2/3 t o 3/4 the l e n g t h of the t a r s u s ; b a s a l f o r e t a r s a l j o i n t 2/3 to 3/4 the l e n g t h o f the second, b a s a l j o i n t o f h i n d t a r s u s i n both sexes s l i g h t l y l o n g e r t h a n the second j o i n t , d i s t a l j o i n t e q u a l to f i r s t and second combined; f o r e c l a w s i n male b l u n t , d i s s i m i l a r i n m i d d l e and h i n d l e g s of male, on a l l l e g s o f f e m a l e ; s t i g m a t i c a r e a o f f o r e w i n g not d i v i d e d by a f i n e l i n e i n t o an upper and lower s e r i e s o f c e l l u l e s ; s t i g m a t i c c r o s s v e i n s u s u a l l y not anastomosed, but s t u n t e d , b a s a l c o s t a l c r o s s -v e i n s u s u a l l y w e l l - d e v e l o p e d ; o u t e r f o r k of Rs of h i n d wing p r e s e n t ; penes r o d - l i k e , s e p a r a t e d a l m o s t t o base; a p a i r of s h o r t s p i n e s , o f t e n o u t c u r v e d s l i g h t l y , u s u a l l y on i n n e r a p i c a l m a r g i n , o f t e n a s i n g l e s p i n e on each lower o u t e r m a r g i n ; s u b a n a l p l a t e of female w i t h a U-shaped c l e f t i n a p i c a l m a r g i n . Nymph; F r o n t of head e m a r g i n a t e , e x p o s i n g mouthparts when viewed d o r s a l l y ; mandible not v i s i b l e d o r s a l l y ; i n n e r c a n i n e l / 4 the l e n g t h of the o u t e r ; s p i n e s on crown of the l a c i n i a - g a l e a ; g i l l s on segments 1-7, d i r e c t l a t e r a l l y ; g i l l s on segment 1 l a r g e s t f i b r i l l a r p o r t i o n v e n t r a l , r e d u c e d t o a few t i n y t h r e a d s ; no f i n g e r l i k e p r o j e c t i o n s on l a m e l l a e ; p o s t e r o - l a t e r a l margins o f abd o m i n a l t e r g i t e s -61-s l i g h t l y p roduced; t a i l s t h r e e . Genotype: Cinyqmula r a m a l e y i ( E c d y u r u s ) Dodds. C IN YG1Y1UL A Key To A d u l t s 1. C r o s s v e i n s margined w i t h broiun 2. C r o s s v e i n s not margined 3. 2. C r o s s v e i n s i n c o s t a l h a l f o f f o r e w i n g o n l y s l i g h t l y margined w i t h brown. UJings t i n g e d w i t h amber a t base and a l o n g c o s t a l margin o f both w ings.. q a r t r e l l i IYlcD C r o s s v e i n s v e r y f i n e and brown, more d i s t i n c t i n p t e r o s t i g m a t i c a r e a . UJings h y a l i n e w i t h t r a c e s of b l a c k i s h s h a d i n g a t extreme bas e . . . . . . . . k o o t e n a i IYlcD 3. V e n t r a l m e d i a l marks absent mimus ( E a t o n ) V e n t r a l m e d i a l marks p r e s e n t 4. 4. One o r more s p i n e s s u b a p i c a l l y on each d i v i s i o n of penes, on i n n e r m a r g i n s . . .....5. L a t e r a l s p i n e s p r e s e n t on lower o u t e r margins of penes par ( E a t o n ) 5. Two l o b e s a t apex o f each d i v i s i o n o f penes, the l o n g e r d i r e c t e d l a t e r a l l y r a m a l e y i (Dodds) A s i n g l e w e l l - d e f i n e d l o b e on apex of each d i v i s i o n o f penes u n i f o r m u s (IYlcD) Key To Nymphs 1. A p i c a l abdominal t e r g i t e s same c o l o u r as the o t h e r s s p . 1 A p i c a l abdominal t e r g i t e s p a l e r than the o t h e r s ..2. 2. A p i c a l abdominal t e r g i t e s w h i t e . Femora brown w i t h a p a l e -62-L-shaped o r V-shaped l o n g i t u d i n a l mark on each b a s a l h a l f . . . . 3 . A p i c a l abdominal t e r g i t e s may be p a l e r t h a n the p r e c e d i n g ones, but each has a narrow dark a n t e r i o r m a r g i n . Femora o c h r e o u s , w i t h two broad brown bands U Q i f o r m d s (IYlcD) 3. P a l e f e m o r a l mark L-shaped , . r a m a l e y i (Dodds) P a l e f e m o r a l mark V-shaped.. sp.2 Unknown: Cinyqmula q a r t r e l l i filcD Cinyqmula mimus ( E a t o n ) Cinyqmula par ( E a t o n ) Cinyqmula k o o t e n a i fflcD CIMYGmULA GARTRELLI (YlcDUNNOUGH Cinyqmula q a r t r e l l i OflcDunnough, Needham, 1935, The B i o l o g y of M a y f l i e s , 388 ( B i b l i o g r a p h y ) A d u l t : A medium s i z e d brown s p e c i e s ; a w i n e - c o l o u r e d p a t c h a n t e r i o r to base of f o r e w i n g from which a p a l e o c h r e o u s dash p r o j e c t s towards the pronotum; wings h y a l i n e ; t i n g e d w i t h amber a t base and a l o n g c o s t a l m argin; c r o s s v e i n s i n c o s t a l h a l f of f o r e w i n g o n l y s l i g h t l y margined w i t h brown; abdominal t e r g i t e 1 deep brown; t e r g i t e s 2-7 p a l e s e m i - h y a l i n e , p o s t e r i o r p o r t i o n s deep r e d d i s h brown; t e r g i t e s 8-10 opaque dark brown, w i t h p a l e l a t e r a l p a t c h e s on t e r g i t e s 8 and 9; s t e r n i t e s l i g h t - y e l l o w i s h brown w i t h p o s t e r i o r m a r g i n s , and o f t e n t h e t h r e e a p i c a l segments, f a i n t l y t i n g e d w i t h r e d d i s h ; f a i n t g a n g l i o n i c m a r k i n g s ; a s i n g l e w e l l d e f i n e d l o b e on apex of each d i v i s i o n of penes, each w i t h a s m a l l v e n t r a l s p i n e -63-on the i n n e r m a r g i n ; median a p i c a l s p i n e s s l i g h t l y s e r r a t e on o u t e r m a r g i n s . Nymph; Unknown D i s t r i b u t i o n : B r i t i s h C o l umbia No specimens of t h i s s p e c i e s were examined. CINYGffiULA KOOTENAI fflcDUNNOUGH Cinyqmula k o o t e n a i fYlcDunnouqh, fflcDunnough, 1943, Can.Ent. 75:3 ( B i b l i o g r a p h y ) A d u l t : Wings h y a l i n e ; w i t h t r a c e s o f b l a c k i s h s h a d i n g a t extreme base; v e n a t i o n f i n e , brown; 4 or 5 e x t r e m e l y f a i n t c r o s s v e i n s b e f o r e t h e b u l l a ; s t i g m a t i c c r o s s v e i n s more d i s t i n c t , w i t h o n l y an o c c a s i o n a l t r a c e o f anastomoses; penes bent outward i n a p i c a l h a l f ; t he v e r y d i s t i n c t i v e s t i m u l i a r e v e r y l o n g , t h i n , and c u r v e d i n w a r d s i n t h e i r a p i c a l p o r t i o n s . Nymphs: Unknown D i s t r i b u t i o n : B r i t i s h C olumbia No specimens of t h i s s p e c i e s were examined. CINYGITIULA ffllMUS (EATON) Cinyqmula mimus ( E a t o n ) , S p i e t h , 1941, Ann. E n t . Soc. Amer., 34:89 ( B i b l i o g r a p h y ) a d u l t : A l a r g e p u r p l i s h brown s p e c i e s ; p a l e y e l l o w i s h o r creamy a r e a s a n t e r i o r and v e n t r a l to wing ba s e s ; wings h y a l i n e , t i n g e d w i t h amber, e s p e c i a l l y on h i n d wing and b a s a l h a l f of f o r e w i n g ; v e n a t i o n l i g h t y e l l o w i s h o r r e d d i s h brown; no margined c r o s s v e i n s ; c l a w s o f f o r e l e g s -64-o f male s i m i l a r ; abdominal t e r g i t e s 2-7 s e m i - h y a l i n e , p a l e p u r p l i s h t o l i g h t brown, a n t e r i o r margins c o l o u r l e s s , p o s t e r i o r margins n a r r o w l y d a r k e r , t e r g i t e s 8-10 opaque, y e l l o w i s h brown, t i n g e d w i t h p u r p l i s h or brown; s t e r n i t e s s i m i l a r to t e r g i t e s , but p a l e r ; no v e n t r a l m e d i a l m a r k i n g s ; penes d i v e r g e n t a l m o s t from base, each d i v i s i o n w i t h a s i n g l e w e l l - d e f i n e d l o b e a t apex; no v e n t r a l sub-a p i c a l s p i n e s , but each p e n i s w i t h a s i n g l e s p i n e on i n n e r m a r g i n . Mymph; Unknown D i s t r i b u t i o n : Utah, Wyoming, Montana, C a l i f o r n i a , B r i t i s h C o l u mbia. No specimens o f t h i s s p e c i e s were examined. CINYGlflULA PAR (EATON.) Cinygmula par ( E a t o n ) , S p i e t h , 1941, Ann. Ent. Soc. Amer., 34:89 fflayo, 1952, Pan. Pac. E n t . 28:182 ( B i b l i o g r a p h y ) A d u l t : A medium s i z e d l i g h t brown s p e c i e s ; c l a w s o f f o r e l e g of male d i s s i m i l a r ; wings h y a l i n e , may be f a i n t l y t i n g e d w i t h p a l e g r e y , d a r k e r a t base and a t s t i g m a , b r o w n i s h a t extreme base; v e n a t i o n y e l l o w i s h brown; no margined c r o s s v e i n s ; abdominal t e r g i t e s 2-7 s e m i - h y a l i n e , l i g h t brown w i t h p a l e d i r t y - w h i t i s h a n t e r i o r m a r g i n s , a n t e r o - l a t e r a l a r e a s , narrow median and submedian s t r e a k s ; s t r e a k s o u t l i n e d i n d a r k e r brown; t e r g i t e s 8-10 opaque brown; s t e r n i t e s p a l e r , g a n g l i o n i c markings on s t e r n i t e s 3-7 s e p i a - b r o w n ; penes each w i t h a l a r g e s p i n e on lower o u t e r m a rgins and a s m a l l e r s p i n e on i n n e r m a r g i n . Nymph: Unknown D i s t r i b u t i o n : B r i t i s h Columbia No specimens o f t h i s s p e c i e s were examined. -65-CINYGMULA RAIYIALEYI (DODDS ) Cinyqmula r a m a l e y i (Dodds), Needham, 1935, The B i o l o g y o f M a y f l i e s , 390 ( B i b l i o g r a p h y ) A d u l t : A medium s i z e d r e d d i s h and p u r p l i s h brown s p e c i e s ; t h o r a x r e d d i s h brown, mesonotum y e l l o w i s h brown w i t h r e d d i s h brown m e d i a n s t r i p e and p u r p l i s h brown p o s t e r o - l a t e r a l a r e a s ; l a t e r a l a r e as of metanotum p u r p l i s h brown; claws o f f o r e l e g of male s i m i l a r ; wings h y a l i n e , amber t i n g e d t h r o u g h o u t ; v e n a t i o n f i n e , r e d d i s h brown; no margined c r o s s v e i n s ; abdominal t e r g i t e s 2-8 l i g h t red-brown, s e m i - h y a l i n e i n a n t e r i o r p o r t i o n s , r e s t p u r p l i s h brown; t e r g i t e 2 w i t h narrow h y a l i n e a n t e r i o r m a r g i n ; t e r g i t e 3 w i t h l / 3 of a n t e r i o r p o r t i o n h y a l i n e ; t e r g i t e s 4-7 w i t h a n t e r i o r l / 2 of a n t e r i o r p o r t i o n s h y a l i n e ; t e r g i t e s 8-10 opaque red-brown; p a l e submedian s t r e a k s o u t l i n e d i n d a r k e r c o l o u r on b a s a l t e r g i t e s ; s t e r n i t e s g r e y i s h , t i n g e d w i t h p a l e brown; p a l e red-brown g a n g l i o n i c m a r k i n g s on s t e r n i t e s 7-9 o n l y ; penes w i t h 2 l o b e s a t apex of each d i v i s i o n , the l a r g e r d i r e c t e d l a t e r a l l y ; a c u r v e d s p i n e s u b a p i c a l l y on i n n e r margin o n l y of each p e n i s . Nymph: Femora brown w i t h a p a l e L-shaped l o n g i t u d i n a l mark on b a s a l h a l f o f each; a p i c a l abdominal t e r g i t e s w h i t e . D i s t r i b u t i o n : Montana, B r i t i s h Columbia No specimens of t h i s s p e c i e s were examined. CINYGMULA UNIFQRMIS (McDUNNOUGH) Cinyqmula u n i f o r m i s (McDunnough), Needham, 1935, The B i o l o g y o f fflay-\u00E2\u0080\u00A2 f l i e s , 392 ( B i b l i o g r a p h y ) . -66-A d u l t : Wings h y a l i n e , u n i f o r m l y s u f f u s e d w i t h l i g h t amber; v e n a t i o n f i n e brown; no margined c r o s s v e i n s ; abdominal t e r g i t e s i n C. q a r t r e l l i b ut brown p o s t e r i o r margin n a r r o w e r , and a n t e r i o r h y a l i n e a r e a s w i d e r , and w i t h no r e d d i s h , t i n g e s ; a p i c a l t e r g i t e s opaque, a l m o s t s e p i a - b r o w n ; t e r g i t e 8 w i t h a narrow b l a c k i s h p o s t e r i o r m a r g i n ; s t e r n i t e s v e r y p a l e o c h r e o u s , 8 and 9 l i g h t y e l l o w - b r o w n ; g a n g l i o n i c m a r k i n g s f a i n t ruddy; each d i v i s i o n o f penes w i t h a w e l l - d e f i n e d a p i c a l l o b e , each b e a r i n g a s m a l l v e n t r a l s u b a p i c a l s p i n e on the i n n e r m a r g i n ; median s p i n e s not s e r r a t e on o u t e r m a r g i n s . Nymph; Femora o c h r e o u s , each w i t h 2 broad brown bands; a p i c a l a bdominal t e r g i t e s may be p a l e r than the o t h e r s , but each has a narrow dark a n t e r i o r m a r g i n . D i s t r i b u t i o n ; B r i t i s h Columbia No specimens o f t h i s s p e c i e s were examined. Cinyqmula s p . 1 A d u l t ; Unknown Nymph; A l l abdominal t e r g i t e s u n i c o l o u r e d . E c o l o g y ; Specimens of t h i s s p e c i e s were t a k e n from the m i d d l e arid edges of a number of l o c a t i o n s on the A l o u e t t e R i v e r . The r i v e r bed i n t h e s e l o c a t i o n s v a r i e d from mud, t h r o u g h sand, g r a v e l , and r o c k s , t o l a r g e b o u l d e r s . They were t a k e n a t a depth of 1 t o 3 f e e t , a l t h o u g f a t one l o c a t i o n , i n q u i e t w a t e r , they were taken from a depth o f 4 to 5 f e e t . The c u r r e n t v a r i e d from q u i e t t o r i p p l e s t o r a p i d s and f a l l s . The specimens were c o l l e c t e d d u r i n g the e n t i r e y e a r . -67-D i s t r i b u t i o n : B r i t i s h C olumbia M a t e r i a l Examined; 3 Nymphs, B r i t i s h C o l u m b i a ; A l o u e t t e R i v e r , VI.2.59 (N. F i l m e r ) 3 Nymphs, Loon C r . (H. L o r z ) . C inyqmula s p . 2 . A d u l t ; Unknown Nymph; I d e n t i c a l t o _C_^_ r a m a l e y i , but p a l e f e m o r a l m arkings d i s t i n c t l y V-shaped, r a t h e r than L-shaped. D i s t r i b u t i o n ; B r i t i s h Columbia M a t e r i a l Examined; 3 Nymphs, B r i t i s h C o l u m b i a : n r . Hell\u00C2\u00ABs .Gate, VI.19.59 (G.G.E. S c u d d e r ) . GENUS EPEORUS EATON Epeorus E a t o n , E a t o n , 1881, E n t . IKlon. (flag., 18:26 ( B i b l i o g r a p h y ) A d u l t ; B a s a l j o i n t of f o r e t a r s u s of male e q u a l t o o r s l i g h t l y l o n g e r than the second j o i n t ; f o r e t a r s u s o f male l o n g e r than the t i b i a , o u t e r f o r k of the Rs of the h i n d wing p r e s e n t ; a p i c a l margin of f o r c e p s base not d e e p l y e x c a v a t e d ; male f o r c e p s 4 - j c i n t e d . Nymph: A f l a t t e n e d , s p r a w l i n g s p e c i e s ; m a x i l l a r y p a l p i 2 - j o i n t e d , 2nd j o i n t l e s s than 4 t i m e s the l e n g t h o f the g a l e a - l a c i n i a ; f i b r i l l a r p o r t i o n o f each p a i r of g i l l s p r e s e n t ; no f i n g e r l i k e p r o j e c t i o n of g i l l l a m e l l a e ; c l a w s not e l o n g a t e d ; 2 t a i l s . -68-SUBGENUS IRON EATON I r o n , Edmunds and A l l e n , 1957, Ann. E n t . Soc. Amer. 50 (4):319 Needham, 1935, The B i o l o g y o f m a y f l i e s , 392 ( B i b l i o g r a p h y ) A d u l t : Eyes of male l a r g e , u s u a l l y c o n t i g u o u s a p i c a l l y ; p o s t e r i o r m argin o f head of female v e r y s l i g h t l y e m a r g i n a t e ; p o s t e r i o r margin o f pronotum somewhat e x c a v a t e d m e d i a l l y ; f o r e l e g o f male as l o n g as o r s l i g h t l y l o n g e r t h a n the body; f o r e femur of male 2/3 as l o n g as the t i b i a , which i s 3/4 t h e l e n g t h o f the t a r s u s ; f o r e femur o f f e m a l e o n l y s l i g h t l y s h o r t e r than the t i b i a ; t a r s u s s u b e q u a l t o femur; i n h i n d l e g of b o t h s e x e s , femur about 3/4 the l e n g t h o f the t i b i a , t a r s u s about l / 2 as l o n g as femur; u s u a l l y a prominent b l a c k mark i n m i d d l e of femora, c l a w s u s u a l l y d i s s i m i l a r ; s t i g m a t i c c r o s s -v e i n s of f o r e w i n g not anastomosed; b a s a l c o s t a l c r o s s v e i n s o f t e n weak and i n d i s t i n c t ; second f o r k o f Rs of h i n d wing a r i s e s basad o f f i r s t f o r k ; second j o i n t of f o r c e p s l o n g e r than 3 r d and 4 t h j o i n t s combined; penes u s u a l l y u n i t e d i n the b a s a l 2/3; a p a i r of median s p i n e s on penes; a p i c a l margin of s u b a n a l p l a t e of female e m a r g i n a t e m e d i a l l y . Nymph: F r o n t a l and l a t e r a l m argins o f head expanded, c o m p l e t e l y c o v e r i n g the m o u t h p a r t s ; labrum s m a l l , 1-1/2 t o 2 tim e s as wide as l o n g , a n t e r o - l a t e r a l c o r n e r s rounded, a n t e r i o r margin w i t h s m a l l m e d i a l e x c a v a t i o n ; i n n e r c a n i n e l / 2 t o 3/4 as l o n g as t h e o u t e r one; l a c i n i a -a b s e n t or r e p r e s e n t e d by 2 t o 3 s h o r t h a i r s ; i n n e r a p i c a l margin of g a l e a - l a c i n i a each w i t h a t r i a d of s l i g h t l y i n c u r v e d s t o u t s p i n e s , each b e a r i n g a s l e n d e r t h r e a d - l i k e appendage a t i t s apex; may be 5-7 s l e n d e r s p i n e s a t the bases of these s p i n e s ; no s p i n e s a l o n g upper margins of m a x i l l a e ; median p o r t i o n o f hypopharynx l o n g e r and n a r r o wer than l a t e r a l p o r t i o n s ; g l o s s a e c o n i c a l , may be s l i g h t l y c o n v e r g e n t a p i c a l l y ; l a t e r a l m argins of pronotum s l i g h t l y d i l a t e d a t o r a n t e r i o r t o m i d d l e ; l e g j o i n t s ' T r i n g e d w i t h h a i r s ; f e m o r a l f l a n g e s harp p o i n t e d o r b l u n t ; c l a w s w i t h 3 t o 6 l a t e r a l a p i c a l p e c t i n a t i o n s ; abdominal t e r g i t e s w i t h a p a i r of s p i n e s a t each p o s t e r o l -a t e r a l a n g l e ; f i b r i l l a r p o r t i o n of each g i l l w e l l d e v e l o p e d , a p p a r e n t l y d o r s a l ; l a m e l l a t e p o r t i o n o f each g i l l n a r r o w l y t h i c k e n e d a l o n g o u t e r m a r g i n , which b e a r s many minute s p i n e s ; each g i l l o v e r l a p s the one b e h i n d i t , o u t e r margins p r e s s e d a g a i n s t the s u r f a c e ; a n t e r i o r l o b e o f f i r s t g i l l w e l l d e v e l o p e d , may or may not meet beneath t h e body; g i l l s o f l a s t segment u s u a l l y approach one a n o t h e r beneath body. Genotype: I r o n lonqimanus Eaton SUBGENUS IRONODES TRAVER I r o n o d e s , Edmunds and A l l e n , 1957, Ann. E n t . Soc. Amer. 50 ( 4 ) : 319 Needham, 1935, The B i o l o g y o f m a y f l i e s , 413 ( B i b l i o g r a p h y ) A d u l t : Eyes of male s m a l l t o moderate, u s u a l l y not c o n t i g u o u s a p i c a l l y ; p o s t e r i o r margin o f head of female d e e p l y e m a r g i n a t e ; f o r e l e g of male s l i g h t l y l o n g e r than body; femur 2/3 as l o n g as t h e t i b i a ; f o r e femur of female s l i g h t l y l o n g e r than t i b i a ; t a r s u s s u b e q u a l t o femur; i n h i n d l e g of b o t h s e x e s , t i b i a s l i g h t l y s h o r t e r than femur; male t a r s u s l / 2 t o 2/3 the l e n g t h of the t i b i a , f e m a l e t a r s u s l / 2 the l e n g t h o f the t i b i a ; c l a w s d i s s i m i l a r ; b a s a l c o s t a l c r o s s v e i n s -70-s t r o n g ; s t i g m a t i c c r o s s v e i n s numerous, s i m p l e , a s l a n t ; p o s t e r i o r b r a n c h of lYi i n f o r e w i n g forms a l m o s t a r i g h t a n g l e w i t h a n t e r i o r b r a n c h ; f o r k s o f Rs o f h i n d wing a r i s e a t about the same p o i n t ; media of h i n d wing f o r k e d about l / 3 from base; second j o i n t o f f o r c e p s l o n g e r than 3 r d and 4 t h combined, o f t e n more o r l e s s bowed near m i d d l e or i n a p i c a l t h i r d ; penes u s u a l l y s e p a r a t e d a l m o s t to base, somewhat compressed, e l o n g a t e , d i v e r g e n t a p i c a l l y ; a s e r i e s o f s m a l l s p i n e s on v e n t r a l s u r f a c e o f each d i v i s i o n ; a p i c a l margin o f s u b a n a l p l a t e o f female s l i g h t l y e m a r g i n a t e . Nymph: L a t e r a l and f r o n t a l margins of head expanded, c o m p l e t e l y c o v e r -i n g the m o u t h p a r t s ; f r o n t a l margin s l i g h t l y e m a r g i n a t e m e d i a l l y , d e n s e l y f r i n g e d w i t h h a i r s ; labrum 1-1/2 to 2 tim e s as wide as l o n g , f r o n t a l margin w i d e l y e x c a v a t e d m e d i a l l y ; a n t e r o - l a t e r a l a n g l e s s l i g h t l y rounded, l a t e r a l margins s l o p i n g toward base; i n n e r c a n i n e s 3/4 t o 7/8 as l o n g as the o u t e r ones; a few h a i r s i n l a c i n i a l r e g i o n ; upper margins o f ma n d i b l e s s l o p e s h a r p l y from bases o f c a n i n e s to molar s u r f a c e s ; a t h i c k e n e d a r e a below and s u b p a r a l l e l t o molar a r e a ; g a l e a - l a c i n i a w i t h a f r i n g e of l o n g h a i r s on o u t e r and upper m a r g i n s ; no t r i a d o f s t o u t s p i n e s a t t i p , but a few s l e n d e r s t r a i g h t s p i n e s ; second j o i n t of m a x i l l a r y p a l p i c l a v a t e , many s e r i e s o f s h o r t s p i n e s c u r v e d a t t i p s i n a p i c a l h a l f ; g l o s s a e s l i g h t l y concave i n i n n e r m a r g i n , s t r o n g l y convex on o u t e r , c l o s e t o g e t h e r and s l i g h t l y c o n v e r g e n t a p i c a l l y ; m e d i a l p o r t i o n o f hypopharynx much narrower and s h o r t e r than l a t e r a l p o r t i o n s ; f r o n t a l margin of pronotum e m a r g i n a t e , l a t e r a l m argins s l i g h t l y expanded, p o s t e r i o r margin w i t h a m e d i a l and 2 sub-m e d i a l e m a r g i n a t i o n s ; a t r a n s v e r s e r i d g e l / 3 d i s t a n c e from a n t e r i o r m argin of pronotum, d i v i d i n g pronotum i n t o a lower a n t e r i o r l / 3 and a h i g h e r p o s t e r i o r 2/3; each coxa w i t h two prominent f l a n g e - l i k e p r o j e c t i o n s ; f e m o r a l f l a n g e s s h o r t and b l u n t ; c l a w s w i t h p e c t i n a t i o n s near apex; g i l l - b e a r i n g abdominal segments o n l y w i t h v e r y s h o r t b l u n t p o s t e r o - l a t e r a l s p i n e s ; t e r g i t e s 1-9 w i t h a row of s u b m e d i a l s p i n e s , each a r i s i n g 1/3 from a n t e r i o r m a r g i n s ; f i b r i l l a r p o r t i o n o f g i l l s w e l l d e v e l o p e d , a p p a r e n t l y d o r s a l ; l a m e l l a t e p o r t i o n s s m a l l , o b o v a t e , f i r s t p a i r s m a l l e s t , s e v e n t h p a i r s l i g h t l y l a r g e r . Genotype: .Ironodes n i t i d u s ( i n I r o n ) Eaton SUBGENUS IRDNQPSIS TRAVER I r o n o p s i s , Edmunds and A l l e n , 1957, Ann. E n t . Soc. Amer. 50 (4) : 319 Needham, 1935, The B i o l o g y o f M a y f l i e s , 420 ( B i b l i o g r a p h y ) A d u l t ; L a r g e p u r p l i s h brown s p e c i e s ; eyes o f male l a r g e , c o n t i g u o u s a p i c a l l y ; p o s t e r i o r m a r g i n of head of female e m a r g i n a t e ; p o s t e r i o r margin o f pronotum d e e p l y e x c a v a t e d m e d i a l l y ; f o r e l e g o f male much l o n g e r than body; f o r e femur of male 3/4 as l o n g as t i b i a ; f o r e femur of female almost as l o n g as t i b i a ; a l l c l a w s d i s s i m i l a r ; s t i g m a t i c c r o s s v e i n s s t r o n g l y anastomosed; may be a l o n g i n t e r c a l a r y between C u l and f i r s t s e t of p a i r e d i n t e r c a l a r i e s ; f o r k s o f Rs of h i n d wing a r i s e a t about the same, p o i n t ; second j o i n t o f f o r c e p s not as l o n g as 3r d and 4 t h combined; penes r o d - l i k e , d i v e r g e n t a t t i p s ; a c l u s t e r o f s m a l l s p i n e s on v e n t r a l s u r f a c e s of each p e n i s some d i s t a n c e below apex; a p i c a l margin o f s u b a n a l p l a t e o f female w i t h a V-shaped median c l e f t . Nymph; F r o n t a l margin o f head and l a t e r a l m a r gins a n t e r i o r t o eyes expanded;, f r o n t a l margin v e r y s l i g h t l y e m a r g i n a t e . m e d i a l l y ; c a n i n e s -72-w i d e r and b l u n t e r than i n I r o n ; a row of h a i r s i n l a c i n i a l r e g i o n of each m a n d i b l e ; a t h i c k e n e d a r e a below and p a r a l l e l to molar a r e a o f each m a n d i b l e , and a n o t h e r below t h i s , on i n n e r m a r g i n , a t r i g h t a n g l e s t o molar a r e a ; g l o s s a e c o n i c a l , d i v e r g e n t a p i c a l l y , w i d e l y s e p a r a t e d a t base; a t r i a d o f s t o u t s p i n e s a t t i p of g a l e a -l a c i n i a ; labrurn d e f l e x e d , a n t e r o - l a t e r a l a n g l e s a n g u l a t e , not rounded, f r o n t a l margin not .emarginate; a n t e r o - l a t e r a l a n g l e s of pronotum rounded; femora, t i b i a e and t a r s i w i t h f r i n g e s of l o n g h a i r s , c l a w s w i t h t h r e e l a t e r a l p e c t i n a t i o n s near a p i c e s ; abdominal t e r g i t e s w i t h p o s t e r o - l a t e r a l e x p a n s i o n s s h o r t and b l u n t ; g i l l s o f 1 s t segment e n l a r g e d , a n t e r i o r l o b e s meeting beneath the body; i n t e r m e d i a t e g i l l s w e l l - d e v e l o p e d , t h i c k e n e d on o u t e r m a r g i n s , and o v e r l a p p i n g t h o s e b e h i n d them; s e v e n t h g i l l s meet beneath the body; f i b r i l l a r p o r t i o n of g i l l s s h o r t , not p r o m i n e n t , a p p a r e n t l y d o r s a l . Genotype; I r o n o p s i s q r a n d i s ( i n I r o n ) fflcDunnough EPEORUS Key To A d u l t s 1. B a s a l c o s t a l c r o s s v e i n s of f o r e w i n g weak. Eyes of male u s u a l l y c o n t i g u o u s 2. B a s a l c o s t a l c r o s s v e i n s of f o r e w i n g s t r o n g . Eyes of male not c o n t i g u o u s Ironodes T r a c e r 3 2. S t i g m a t i c c r o s s v e i n s s l a n t i n g . S t i g m a t i c c r o s s v e i n s of f o r e wing more or l e s s s t r o n g l y anastomosed, sometimes f o r m i n g 2 s e r i e s of c e l l u l e s I r o n o p s i s T r a v e r 4 S t i g m a t i c c r o s s v e i n s not s l a n t i n g . S t i g m a t i c c r o s s v e i n s of f o r e w i n g not anastomosed I r o n Eaton 5 3. w'ing membrane f a i n t l y a m b e r - t i n g e d , s t i g m a t i c a r e a smoky. -73-fflesonotum b l a c k - b r o w n f l a v i p e n n i s T r a v e r lYlesonotum l i g h t brown. S m a l l s p i n e s on v e n t r a l s u r f a c e o f penes r e l a t i v e l y few i n number \u00E2\u0080\u00A2 q r a n d i s (IYlcD) lYlesonotum b l a c k - b r o w n . S m a l l s p i n e s on v e n t r a l s u r f a c e of penes v e r y numerous permaqnus T r a v e r Abdominal t e r g i t e s 2-7 y e l l o w i s h , t e r g i t e s may be f a i n t l y smoky. T h o r a c i c p l e u r a e w i t h d i s t i n c t b l a c k i s h m a r k i n g s . G e n i t a l i a of a l b e r t a e type ( f i g . 3) d u l c i a n a IYlcD Abdominal t e r g i t e s 2-7 brown. No dark marks on p l e u r a e . G e n i t a l i a ' not of a l b e r t a e t y p e 6. V e n a t i o n dark brown. G e n i t a l i a of d e c e p t i v u s t y p e ( f i g . 3) d e c e p t i v u s (IYlcD) V e n a t i o n p a l e brown. G e n i t a l i a o f longimanus ( f i g . 3) o r of p l e u r a l i s t y p e ( f i g . 3) longimanus ( E a t o n ) Key To Nymphs T r i a d of s t o u t s p i n e s p r e s e n t a t t i p of g a l B a - l a c i n i a 2. No t r i a d of s p i n e s on g a l e a - l a c i n i a I r onodes Trav.e-r 3 A n t e r i o r margin of head e n t i r e . Median abdominal row of h a i r s p o o r l y d e v e l o p e d o r ab s e n t . A n t e r i o r p a i r o f g i l l s v a r i a b l e . G i l l s u s u a l l y t h i n and l i g h t , a n t e r i o r and o u t e r margins not n o t i c e a b l y d a r k e r . . . . . I r o n Ea\u00E2\u0080\u009Eton 4 A n t e r i o r margin o f head s l i g h t l y e m a r g i n a t e . Dense row of l o n g s e t a e on median l i n e o f abdominal t e r g i t e s . A n t e r i o r g i l l s meet beneath the body. G i l l s t h i c k and darkened, e s p e c i a l l y on the a n t e r i o r and o u t e r margins I r o n o p s i s T r a v e r 6 Body dark b l a c k i s h brown. A l l j o i n t s o f l e g s c o n c o l o u r o u s , no p o r t i o n darker, than the o t h e r s f l a v i p e n n i s T r a v e r A l l t e r g i t e s u n i c o l o u r e d brown. A p i c a l h a l f of t a r s i d a r k e r -74-t h an the r e s t of the l e g s . . . . . . . . . sp\u00E2\u0080\u00A2 1 4. A n t e r i o r l o b e s of f i r s t g i l l s not g r e a t l y p r o l o n g e d , and so l a c k much of meeting beneath the the body, (flay or may not be a wedge-shaped p a l e mark on the median l i n e of the meso-notum. 5. A n t e r i o r l o b e s of f i r s t g i l l s meet beneath the body. No p a l e median l i n e on mesonotum .7. 5. liiedge-shaped p a l e mark on median l i n e of mesonotum p r e s e n t , w i d e s t near a n t e r i o r margin d e c e p t i v u s (McD) UJedge-shaped p a l e mark on median l i n e of mesonotum a b s e n t . . . s p . 5 6. Three l a t e r a l p e c t i n a t i o n s near apex o f each claw.. G i l l s on 7 t h segment meet beneath the body...... q r a n d i s (McD) No l a t e r a l p e c t i n a t i o n s near apex of each c l a w . G i l l s on 7th segment do not meet beneath the body permaqnus T r a v e r 7. A n t e r i o r margin of a l l s t e r n i t e s w i t h a dark t r a n s v e r s e s t r e a k on each s i d e of the median l i n e . Two dark s m a l l d o t s near m i d d l e of s t e r n i t e 9. Three t e e t h on claw lonqimanus ( E a t o n ) No dark s t r e a k s on s t e r n i t e s . No dark d o t s on s t e r n i t 9. Less than t h r e e t e e t h on the c l a w . . . . . .8. 8. Media], p r o j e c t i o n of a n t e r i o r l o b e of the f i r s t p a i r of g i l l s narrow and p o i n t e d . G i l l s s e p a r a t e d 9. M e d i a l p r o j e c t i o n of a n t e r i o r l o b e s of f i r s t p a i r of g i l l s b r o a d l y rounded. A l l g i l l s o v e r l a p p i n g t o form a l i g h t s u c t i o n d i s c sp. 2 9. Legs n o t banded. sp. 3 Legs banded sp. 4 -75-Unknown: I r o n d u l c i a n a McDunnough EPEORUS DECEPTIVUS (McDUNNOUGH) Epeorus deceptiv/us (McDunnough), Needham, 1935, The B i o l o g y of May-f l i e s , 399 ( I r o n ) ( B i b l i o g r a p h y ) A d u l t : A l i g h t brown s p e c i e s ; no markings on femora; f o r e l e g o f male much l o n g e r t h a n body; t i b i a s l i g h t l y more th a n 1-1/2 as l o n g as femur; wings h y a l i n e , v e n a t i o n f i n e , l i g h t brown; may be a f a i n t brown s t a i n i n s t i g m a t i c a r e a ; c o s t a l c r o s s v e i n s i n b a s a l a r e a i n d i s t i n c t ; abdominal t e r g i t e s 2-7 s e m i - h y a l i n e , 8-10 opaque; a n t e r i o r p o r t i o n s p a l e brown; p o s t e r i o r p o r t i o n s p u r p l i s h brown; p o s t e r i o r m argins and a n t e r i o r p r o j e c t i o n s from them d a r k e r p u r p l i s h brown; 8-10 may have opaque p i n k i s h w h i t e m a r k i n g s ; s t e r n i t e s p a l e r ; s m a l l o v a l brown g a n g l i o n i c m a r k i n g s ; penes may be widened s u b a p i c a l l y , l a t e r a l l o b e s p r o m i n e n t , or may be l o n g , s l e n d e r , f i n g e r - l i k e , l a t e r a l l o b e s f o l d e d f l a t and b a r e l y n o t i c e a b l e ; median s p i n e s l o n g , s l e n d e r and s l i g h t l y i n c u r v e d . Nymph: Wedge-shaped p a l e mark on median l i n e o f mesonotum, w i d e s t p o r t i o n near the a n t e r i o r margin; f l a n g e on femora 2 and 3 b l u n t a t t i p ; a n t e r i o r l o b e s o f 1 s t p a i r of g i l l s not g r e a t l y p r o l o n g e d or m e e t i n g beneath the body; o u t e r p o s t e r o - l a t e r a l s p i n e s on the m i d d l e abdominal t e r g i t e s s h o r t and b l u n t , n ot more than l / 4 as l o n g as the t e r g i t e , and about as l o n g as t h e i r w i d t h a t base. -76-D i s t r i b u t i o n ; B r i t i s h Columbia No specimens o f t h i s s p e c i e s were examined. EPEORUS DULCIANA (McDUNNOUGH ) Epeorus d u l c i a n a (lYlcDunnough), Needham, 1935, The B i o l o g y o f lYlay-f l i e s , 401 ( I r o n ) ( B i b l i o g r a p h y ) A d u l t ; Head y e l l o w i s h , r e d p a t c h e s on head, l a t e r a l a r e a s o f a n t e r i o r p o r t i o n of mesonotum; femora w i t h median b l a c k i s h s p o t s and narrow a p i c a l red-brown bands; f o r e femur s l i g h t l y s h o r t e r than t i b i a ; wings h y a l i n e ; v e n a t i o n y e l l o w i s h i n male, c r o s s v e i n s , e x c e p t i n s t i g m a t i c a r e a , i n d i s t i n c t ; humeral c r o s s v e i n s near s u b c o s t a b l a c k ; i n f e m a l e , v e n a t i o n f i n e , dark brown, c r o s s v e i n s d i s t i n c t ; a b dominal t e r g i t e s y e l l o w i s h to o l i v e brown, p o s t e r i o r margins n a r r o w l y b l a c k i s h ; s t e r n i t e s p a l e r . Nymph; Unknown D i s t r i b u t i o n : B r i t i s h Columbia No specimens o f t h i s s p e c i e s were examined. EPEORUS FLAUIPENNIS TRAVER Epeorus f l a v i p e n n i s T r a v e r , Needham, 1935, The B i o l o g y o f M a y f l i e s , 418 ( I r o n o d e s ) ( B i b l i o g r a p h y ) A d u l t : A dark brown s p e c i e s ; eyes l a r g e , a l m o s t c o n t i g u o u s a p i c a l l y ; head w i t h deep r e d m a r k i n g s ; a c o n s p i c u o u s creamy p a t c h c o n t a i n i n g a narrow r e d d i s h s t r e a k a n t e r i o r to base of f o r e w i n g ; a r e d s p o t above f o r e c o x a ; a s m a l l e r creamy p a t c h a n t e r i o r t o base of h i n d wing; -77-wings h y a l i n e , p a l e amber; v e n a t i o n dark brown except l o n g i t u d i n a l v e i n s of c o s t a l margin which are amber-brown; s t i g m a t i c a r e a smoky brown; i n f e m a l e , e n t i r e wing deep g r e e n i s h amber; abdominal t e r g i t e s 2-7 s e m i - h y a l i n e , dark brown w i t h a f a i n t red-brown t i n g e ; a n t e r i o r m argins p a l e r , p o s t e r i o r margins opaque dark brown; p l e u r a l f o l d n a r r o w l y dark brown; t e r g i t e s 8-10 opaque deeper brown; s t e r n i t e 9 b r i g h t red-brown. Mymph; D o r s a l l y b l a c k i s h brown; v e n t r a l l y y e l l o w i s h ; l e g s c o n c o l o u r o u s w i t h w h i t e marks b a s a l l y on femora; g i l l s p u r p l i s h b l a c k ; t r a c h e a e i n d i s t i n c t . D i s t r i b u t i o n : B r i t i s h C olumbia No specimens of t h i s s p e c i e s were examined. EPEORUS GRANDIS (McDUNNOUGH) Epeorus q r a n d i s (McDunnough), Needham, 1935, The B i o l o g y o f M a y f l i e s , 421 ( I r o n o p s i s ) ( B i b l i o g r a p h y ) A d u l t : A l i g h t brown s p e c i e s , w i t h a d a r k e r abdomen; two prominent b l a c k l i n e s i n a l i g h t . o l i v e brown p a t c h a n t e r i o r t o wing r o o t s , f o r e femora b l a c k i s h brown, p a l e r a t base, may be shaded w i t h o l i v e brown w i t h f a i n t b l a c k p e n c i l l i n g s ; wings h y a l i n e ; v e n a t i o n f i n e , d a r k ; s t i g m a t i c a r e a f a i n t l y b r o w n - t i n g e d ; humeral c r o s s v e i n f a i n t l y d a r k ; c r o s s v e i n s s t r o n g l y anastomosed; abdominal t e r g i t e s deep brown w i t h p a l e y e l l o w i s h l a t e r a l margins and p a l e y e l l o w i s h submedian s p o t s on p o s t e r i o r m a rgins o f segments 4 to 8, s m a l l e r on t e r g i t e 4; -78-t e r g i t e s 9 and 10 l a r g e l y y e l l o w i s h ; p a l e a r e a s may be o b s c u r e d by r e d d i s h s h a d i n g ; s t e r n i t e s p u r p l i s h brown, p a l e r p o s t e r i o r l y ; r e l a t i v e l y few s m a l l s p i n e s on v e n t r a l s u r f a c e s of each d i v i s i o n of penes. Nymph: Deep p u r p l i s h brown s p e c i e s ; l a t e r a l m argins of pronotum y e l l o w i s h f r i n g e o f l o n g h a i r s on femur, t i b i a and t a r s u s ; t h r e e l a t e r a l p e c t i n -a t i o n s near apex of each c l a w ; median a r e a s of t e r g i t e s 1 t o 4 and 8 t o 9 y e l l o w i s h ; s t e r n i t e mahogany brown m e d i a l l y , p a l e l a t e r a l l y , w i t h a s e r i e s of dark l a t e r a l marks a t the edges of the median dark a r e a s ; g i l l s o f 7 t h segment meet beneath the body. D i s t r i b u t i o n : B r i t i s h C o l u m b i a , A l b e r t a , C a l i f o r n i a , Montana No specimens of t h i s s p e c i e s were examined. EPEORUS LONGIMANUS (EATON) Epeorus lonoimanus ( E a t o n ) , S p i e t h , 1941, Ann. E n t . Soc. Amer. 34:88 ( I r o n ) ( B i b l i o g r a p h y ) A d u l t : A p a l e b r o w n i s h s p e c i e s ; femora w i t h a round b l a c k s p o t near m i d d l e ; wings h y a l i n e ; v e n a t i o n l i g h t b r o w n i s h amber; v e n a t i o n of h i n d wing p a l e r ; f o r e c l a w s d i s s i m i l a r ; abdominal t e r g i t e s 2-7 s e m i -h y a l i n e , p o s t e r i o r m a rgins and s h a d i n g a l o n g m i d - d o r s a l l i n e p u r p l i s h brown; the dark b o r d e r s do not e x t e n d t o the p o s t e r o - l a t e r a l a n g l e s , but an o b l i q u e b l a c k l i n e may e x t e n d from t h i s band o b l i q u e l y t o the p l e u r a l f o l d ; median l i n e n a r r o w l y p a l e , w i t h a d a r k e r s t r e a k on each s i d e ; p a l e submedian l u n a t e marks l i e on each s i d e w i t h i n the shaded a r e a s ; t e r g i t e s 8-10 opaque; s t e r n i t e s p a l e y e l l o w , nerve c o r d and g a n g l i a w h i t i s h and opaque, sometimes t r a c e s of p a l e o b l i q u e sub--79-median s t r e a k s on b a s a l and m i d d l e segments; each d i v i s i o n o f penes w i t h an e r e c t a p i c a l l o b e and a l a r g e r l a t e r a l l o b e , b e a r i n g a sharp l a t e r a l s p i n e ; penes bear a. median p a i r o f s t r o n g s p i n e s w i t h d i v e r g e n t t i p s . Nymph: \u00E2\u0080\u00A2 F l a n g e on femora 2 and 3 b l u n t a t t i p ; t h r e e t e e t h on c l a w s ; o u t e r p o s t e r o - l a t e r a l s p i n e s on m i d d l e abdominal segments s h o r t and b l u n t , not more than l / 4 as l o n g as the r e s p e c t i v e segments, and about as wide a t t h e i r b a s s s as l o n g ; a n t e r i o r margins of a l l s t e r n i t e s w i t h a.dark t r a n s v e r s e s t r e a k on each s i d e of the median l i n e ; 2 dark s m a l l s p o t s near the m i d d l e of s t e r n i t e 9.' D i s t r i b u t i o n : C o l o r a d o , Wyoming, Utah, Montana, A l b e r t a , B r i t i s h C o l u m bia. No specimens of t h i s s p e c i e s were examined. EPEORUS PERfflAGNUS (TRAVER) Epeorus permapnus ( T r a v e r ) , Needham, 1935, The B i o l o g y of M a y f l i e s , 423 ( I r o n o p s i s ) ( B i b l i o g r a p h y ) A d u l t : A dark brown s p e c i e s ; y e l l o w i s h a r e a c o n t a i n i n g a s i n g l e s h o r t b l a c k s t r e a k a n t e r i o r t o r o o t s of f o r e w i n g ; wings h y a l i n e ; l o n g i t u d i n a l v e i n s Sc, C and R t h i c k e n e d , dark r e d d i s h t o p u r p l i s h brown, e x c e p t bases o f Sc and R and base and a p i c a l t h i r d of C, which are y e l l o w i s h ; o t h e r l o n g i t u d i n a l v e i n s f i n e r , l i g h t red-brown; c r o s s v e i n s f i n e , y e l l o w i s h t o p a l e red-brown; humeral c r o s s v e i n p a l e ; abdominal t e r g i t e s y e l l o w i s h to o l i v e brown, w i t h b l a c k - b r o w n p a t c h e s ; . t e r g i t e s 2 and 3 w i t h 2 l a r g e p a t c h e s each, l e a v i n g p a l e l a t e r a l margins and median -89-l i n e ; t e r g i t e s 4 and 5 w i t h s m a l l e r p a t c h e s , l a t e r a l m argins i r r e g u l a r , median l i n e o b s c u r e d ; t e r g i t e s 6-8 w i t h dark median t r i a n g l e s , apex p o i n t i n g p o s t e r i o r l y , e x t e n d i n g 3/4 the l e n g t h of each t e r g i t e , w i t h a dark s p o t i n each p a l e l a t e r a l a r e a ; t e r g i t e s 9- and 10 r e d d i s h brown, a n t e r i o r margins n a r r o w l y b l a c k ; l a t e r a l b l a c k s p o t s on 9, a b l a c k median l i n e and median p o s t e r i o r margin on 10; s t e r n i t e s o l i v e brown, b a s a l s t e r n i t e s and s t e r n i t e 8 shaded w i t h r e d brown; s t e r n i t e 9 deeper brown, i n t e r m e d i a t e s t e r n i t e s each w i t h a round smoky s p o t near a n t e r o - l a t e r a l a n g l e s , s p o t s i n each s t e r n i t e c o n n e c t e d by a smoky t r a n s v e r s e band; penes w i t h numerous s m a l l s p i n e s on v e n t r a l s u r f a c e of each d i v i s i o n . Nymph: No l a t e r a l p e c t i n a t i o n s near apex of each c l a w ; g i l l s o f 7 t h segment do not meet beneath the body. E c o l o g y : Specimens o f t h i s s p e c i e s were t a k e n from t h e m i d d l e and edge o f a number o f l o c a t i o n s on the A l o u e t t e R i v e r . The stream bed v a r i e d from mud, t h r o u g h sand, g r a v e l and l a r g e and s m a l l r o c k s , to b o u l d e r s . The depth of the r i v e r i n t h e s e l o c a t i o n s v a r i e d from 1 to 3 f e e t , and t h e c u r r e n t was i n most c a s e s a moderate r i p p l e , a l t h o u g h specimens were a l s o found i n r a p i d s and under f a l l s , and i n q u i e t w a t e r . The specimens c o l l e c t e d i n t h i s l a t t e r l o c a t i o n may have been washed t h e r e by the s w i f t e r water i n the m i d d l e o f the r i v e r . The specimens were c o l l e c t e d d u r i n g the e n t i r e y e a r . D i s t r i b u t i o n : Oregon, B r i t i s h Columbia - 8 1 -f f l a t e r i a l Examined: 2 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) VI.2.59 (N. F i l m e r ) ; 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) V.26.59 (N. F i l m e r ) . Epeorus s p. 1 A d u l t : Unknown Nymph: A p i c a l h a l f o f t a r s i d a r k e r than the r e s t o f the l e g s ; t e r g i t e s u n i c o l o u r e d brown, no t r a c h e a t i o n on g i l l s ; g e n e r a l d e s c r i p t i o n as f o r subgenus I r o n o d e s . D i s t r i b u t i o n : B r i t i s h Columbia M a t e r i a l Examined: 3 Nymphs, B r i t i s h C o l u mbia: Loon Creek ( C l i n t o n ) , VI.16.56 (H. L o r z ) ; 8 Nymphs, B r i t i s h C o l u m b i a : n r . H e l l ' s Gate, VI.19.59 (G.G.E. S c u d d e r ) . Epeorus sp. 2 A d u l t : Unknown Nymph: F r i n g e on a n t e r i o r margin of the froms; no p a l e median l i n e on mesonotum; l e s s than 3 t e e t h on each c l a w ; no dark s t r e a k s o r d o t s on the abdominal s t e r n i t i s ; a n t e r i o r l o b e s of f i r s t p a i r o f g i l l s b r o a d l y rounded and meet beneath the body; a l l g i l l s o v e r l a p the f o l l o w i n g p a i r ; and l a s t p a i r meet beneath the body to form a s t r o n g s u c t i o n d i s c ; o t h e r taxonomic c h a r a c t e r i s t i c s as f o r the subgenus I r o n . -82-E c o l o q y : Nymphs of t h i s s p e c i e s were t a k e n from the m i d d l e and edges of 5 l o c a t i o n s on t h e A l o u e t t e R i v e r , always from a depth o f one t o two f e e t . The s u b s t r a t e c o n s i s t e d of g r a v e l , r o c k s , b o u l d e r s , and b e d r o c k . In a l l c a s e s e x c e p t one, the c u r r e n t was v e r y r a p i d . The e x c e p t i o n was a q u i e t g r a v e l - l i n e d p o o l , i n t o which the nymphs had no doubt been washed by the t u r b u l e n c e of the c u r r e n t . A l l nymphs were c o l l e c t e d d u r i n g 3une, August, and November. D i s t r i b u t i o n : B r i t i s h C olumbia M a t e r i a l Examined: 3 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) VI.2.59 ( N . J . F i l m e r ) ; 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) V I I I . 1 8 . 5 9 (N.3. F i l m e r ) ; 1 Nymph, B r i t i s h C o l u m b i a : Loon Creek ( C l i n t o n ) , VI.16.59 (H. L o r z ) ; 5 Nymphs, B r i t i s h C o l u m b i a : n r . H e l l ' s Gate, VI.19.59 (G.G.E. S c u d d e r ) ; 8 Nymphs, B r i t i s h C o l u m b i a : Smith F a l l s H a t c h e r y Creek, C u l t u s Lake, VI.12.? (H. L o r z ) . Epeorus sp. 3 A d u l t : Unknown Nymph: Legs not banded a l t e r n a t e l y l i g h t and d a r k ; l e s s t h a n 3 t e e t h on each c l a w ; no p a l e l i n e on mesonotum; g i l l s l a m e l l a t e , s e p a r a t e d , not f o r m i n g a s u c t i o n d i s c ; a n t e r i o r l o b e of 1 s t p a i r of g i l l s narrow and p o i n t e d , meet beneath the body; abdominal s t e r n i t e s w i t h no dark s t r e a k s or. d o t s ; g e n e r a l d e s c r i p t i o n as f o r subgenus I r o n . -83-E c o l o q y t Nymphs o f t h i s s p e c i e s were c o l l e c t e d from the m i d d l e and edges o f a number of l o c a t i o n s on the A l o u e t t e R i v e r . G e n e r a l l y they were t a k e n a t depth of one t o two f e e t , a l t h o u g h they were a l s o t a k e n a t depths o f two i n c h e s and f i v e f e e t . The stream bed i n c l u d e d mud, s i l t , s and, g r a v e l , r o c k s , b o u l d e r s , and b e d r o c k . The c u r r e n t was u s u a l l y r a p i d o r r i p p l y ; a l t h o u g h i n two c a s e s the water was q u i e t and s l o w . They were t a k e n the year round. D i s t r i b u t i o n : B r i t i s h Columbia f f l a t e r i a l Examined; 2 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) \u00E2\u0080\u00A2 \u00E2\u0080\u00A2 VI.2.59 (N.3. F i l m e r ) Epeorus sp. 4 A d u l t : Unknown Nymph: Uecy s i m i l a r t o Epeorus s p . 3 but l e g s banded a l t e r n a t e l y l i g h t and d a r k ; g i l l s v e r y l a r g e ; p o s t e r o - l a t e r a l a n g l e s o f the abdominal t e r g i t e s bear two sharp s p i n e s each. E c o l o g y : T h i s s p e c i e s was ta k e n from the m i d d l e of 3 l o c a t i o n s on the A l o u e t t e R i v e r , a l l a t a depth of one t o two f e e t . The s u b s t r a t e c o n s i s t e d of g r a v e l , r o c k s , b o u l d e r s , and bedr o c k . In a l l c a s e s the c u r r e n t was r a p i d . A l l specimens were c o l l e c t e d i n August. D i s t r i b u t i o n : B r i t i s h Columbia -84-ITIaterial Examined: 2 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.), V I I I . 2 6 . 5 9 ( N . J . F i l m e r ) . Epeorus sp. 5 A d u l t : Unknown Nymph: Very s i m i l a r to E. deceptiv/us, but l a c k i n g the wedge-shaped p a l e mark on t h e mesonotum. D i s t r i b u t i o n : B r i t i s h Columbia M a t e r i a l Examined: 3 Nymphs, B r i t i s h C o l u m b i a : n r . H e l l ' s Gate, VI.19.59, (G.G.E. Scud d e r ) GENUS HEPTAGENIA WALSH H e p t a q e n i a , Needham, 1935, The B i o l o g y o f M a y f l i e s , 335 ( B i b l i o g r a p h y ) A d u l t : Eyes o f male u s u a l l y l a r g e , not c o n t i g u o u s a p i c a l l y , pronotum d e e p l y e x c a v a t e d on p o s t e r i o r margin m e d i a l l y ; f o r e l e g of male l o n g e r than body;of f e m a l e , about 3/4 the l e n g t h of the body; f o r e femur of male s u b e q u a l t o or s l i g h t l y s h o r t e r than the t i b i a ; t a r s u s about 1-1/4 t i m e s the l e n g t h o f the t i b i a ; b a s a l j o i n t o f f o r e t a r s u s of male l / 6 to l / 3 as l o n g as the second j o i n t ; f o r e femur of female s u b e q u a l t o t i b i a ; t a r s u s about 3/4 the l e n g t h o f t h e t i b i a ; b a s a l t a r s a l j o i n t about l / 2 the l e n g t h of t h e second j o i n t ; i n h i n d l e g of both s e x e s , t i b i a about 3/4 the l e n g t h o f the femur; t a r s u s s l i g h t l y more th a n l / 2 the l e n g t h o f the t i b i a ; a l l c l a w s d i s s i m i l a r ; t y p i c a l H e ptagenine wing v e n a t i o n ; s t i g m a t i c c r o s s v e i n s not anastomosed or s l a n t e d , Of o f Rs of h i n d wing p r e s e n t ; a p i c a l margin of f o r c e p s -85-base o f male u s u a l l y s l i g h t l y e m a r g i nate m e d i a l l y , may be d e e p l y e m a r g i n a t e , o r convex; f o r c e p s 4 - j o i n t e d ; penes u s u a l l y u n i t e d i n b a s a l h a l f of t u j o - t h i r d s , not d i s t i n c t l y L-shaped, d i s t a l p o r t i o n s d i v e r g e n t a p i c a l l y ; u s u a l l y each d i v i s i o n w i t h an a p i c a l l o b e and a l a t e r a l l o b e - l i k e e x t e n s i o n o f t e n b e a r i n g a prominent m a r g i n a l s p i n e ; a p a i r o f s t o u t s p i n e s between d i v i s i o n s ; one t o t h r e e p a i r s of s l e n d e r s p i n e s may be on or near the i n n e r m a r g i n o f each d i v i s i o n , near apex; s u b a n a l p l a t e of female w e l l d e v e l o p e d , o b t u s e l y o r r e t u s e l y rounded i n i t s a p i c a l m a r g i n . Nymph: Head d e p r e s s e d , o f t e n l a r g e f o r body; f r o n t e n t i r e o r v e r y s l i g h t l y e m a r g i n a t e ; labrum more than f o u r t i m e s as wide as l o n g , e x t e n d i n g 2/3 t o 3/4 the d i s t a n c e a l o n g the a n t e r i o r margin of the head; no c h i t i n i z e d a r e a s on m a n d i b l e s ; i n n e r c a n i n e o f r i g h t m a n d ible at l e a s t 3/4 as l o n g as the o u t e r ; c a n i n e s s u b e q u a l on l e f t m a n d i b l e : 2 o r 3 b l u n t t e e t h a t t i p of each o u t e r c a n i n e ; l a c i n i a o f r i g h t m a n d ible may be r e p r e s e n t e d by a row of l o n g h a i r s , o f the l e f t by a l a r g e s l e n d e r s p i n e , or on bo t h m a n d i b l e s by 2 o r 3 l o n g s l e n d e r s p i n e s ; p e c t i n a t e s p i n e s on crown of g a l e a - l a c i n i a ; m a x i l l a r y p a l p i 2-segmented, second j o i n t s h o r t e r t h a n 4 t i m e s the l e n g t h o f the g a l e a - l a c i n i a and not v i s i b l e d o r s a l l y ; . p a l p i s l e n d e r , many l o n g h a i r s near t i p of d i s t a l j o i n t ; g l o s s a e of labrum s t r o n g l y a r c h e d away from each o t h e r , may converge a t t i p s ; . l a t e r a l s p i n e s of abdominal t e r g i t e s v a r i a b l e ; f i l a m e n t o u s p o r t i o n o f g i l l s w e l l d e v e l o p e d , d i r e c t e d v e n t r a l l y ; l a m e l l a t e p o r t i o n s d i r e c t e d l a t e r a l l y , not c o n v e r i n g beneath the body; 1 s t and 7 t h g i l l s s m a l l e r t h a n i n t e r m e d i a t e g i l l s , -86-7 t h l a r g e r than the 1 s t ; f i b r i l l a r p o r t i o n may be w a n t i n g on segment 7; no f i n g e r l i k e p r o j e c t i o n s on g i l l l a m e l l a e ; 3 t a i l s , e q u a l i n l e n g t h . Genotype; H e p t a q e n i a f l a v e s c e n s Walsh HEPTAGENIA Key To A d u l t s 1. ' Abdominal t e r g i t e s p a l e 2. Abdominal t e r g i t e s p a t t e r n e d w i t h brown or p u r p l i s h - b r o w n 3. 2. Abdominal t e r g i t e s p a l e creamy to y e l l o w i s h w h i t e , 2-6 semi-h y a l i n e , 7-10 opaque, the l a t t e r more d i s t i n c t l y h y a l i n e . W i t h i n the dark band on each s t e r n i t e are two p a l e d o t s , one on each s i d e of the median l i n e near c e n t e r o f each s t e r n i t e , and two p a l e o b l i q u e median dashes from a n t e r i o r m a r g i n . V e i n s p a l e . G e n i t a l i a of s i m p l i c o i d e s t y p e ( f i g . 3 ) . s i m p l i c o i d e s IYlcD Abdominal segments p a l e , 2-7 s e m i - h y a l i n e , 8-10 opaque. P o s t e r i o r margins o f t e r g i t e s 2-7 smoky grey o r b r o w n i s h , t e r g i t e s 8-10 t i n g e d w i t h p i n k . S t e r n i t e s p a l e y e l l o w i s h . V e i n s b l a c k . G e n i t a l i a o f e l e g a n t u l a type ( f i g . 3) e l e q a n t u l a ( E a t o n ) 3. T h o r a c i c notum brown, w i t h a deeper brown m i d - d o r s a l s t r i p e , most e v i d e n t on a n t e r i o r p o r t i o n of mesonotum. Abdominal t e r g i t e s v e r y p a l e b r o w n i s h , 2-7 w i t h a dark p u r p l i s h - b r o w n median s t r i p e e n c l o s i n g a p a l e narrow m i d - d o r s a l l i n e , on p o s t e r i o r margins a narrow dark band of the same c o l o u r , w i t h submedian broad dark bands p r o j e c t i n g f o r w a r d from i t , but not a t t a i n i n g the a n t e r i o r m a r g i n . The dark d o r s a l and submedian s t r i p e s may c o a l e s c e t o form a s i m p l e dark -87-s h a d i n g , or w i t h p a l e r l u n a t e marks s u b m e d i a l l y from the a n t e r i o r m a r g i n . T e r g i t e s 8-10 opaque, l i g h t r e d d i s h brown. S t e r n i t e s p a l e . . s o l i t a r i a fflcD Not as above 4. T h o r a c i c notum l i g h t brown, w i t h two p u r p l i s h p a t c h e s on the p l e u r a a n t e r i o r to m e s o t h o r a c i c wing b a s e s . T e r g i t e s p a l e brown w i t h a p u r p l i s h t i n g e , 7-10 dark p u r p l i s h - b r o w n . S t e r n i t e s p i n k i s h . . . sp. Not as above.... 5 T h o r a c i c notum brown. A l l t e r g i t e s brown w i t h a p a l e a r e a on l a t e r a l p o s t e r i o r b o r d e r s . S t e r n i t e s p a l e , w i t h d a r k e r g a n g l i o n i c m a r k i n g s ..sp. 2 Not as above 6 T h o r a c i c notum brown.. T e r g i t e s brown w i t h a t h i n p a l e median l i n e , f l a n k e d by two p a l e submedian d o t s . S t e r n i t e s p a l e .sp. 3 T h o r a c i c notum dark brown. T e r g i t e s v e r y dark brown, w i t h no p a l e m a r k i n g s . . P a l e spot on m i d l i n e o f mesonotum. s p . 4 Key To Nymphs Pronotum w i d e s t a t a n t e r i o r m a r g i n . F i l a m e n t o u s p o r t i o n o f 7 t h p a i r o f g i l l s p r e s e n t . Claws l a c k i n g p e c t i n a t i o n s . No abdominal s p i n e s on segment 8 3. Pronotum w i d e s t a t or near the m i d d l e . F i l a m e n t o u s p o r t i o n of 7th p a i r of g i l l s w a n t i n g . Claws w i t h or w i t h o u t p e c t -i n a t i o n s . Segment 8 w i t h or w i t h o u t abdominal s p i n e s . . . . . . 2 . 2. Claws w i t h p e c t i n a t i o n s . Abdominal s p i n e s on Segment 8. T e r g i t e s 8-10 l a r g e l y dark.' s i m p l i c o i d e s IYlcD Claws w i t h o u t p e c t i n a t i o n s . No abdominal s p i n e s on segment 8. T e r g i t e 8 l a r g e l y p a l e sp.4 3. P a l e submedian s t r e a k s c o a l e s c e on t e r g i t e s 8 and 9 t o form a l a r g e p a l e b l o t c h on each e l e q a n t u l a ( E a t o n ) No p a l e submedian s t r e a k s .4. 4. T e r g i t e s 8-10 or 9-10 c o m p l e t e l y p a l e . No p a l e s p o t s on head. F r o n t a l p l a t e does not e x t e n d beyond eyes s p . 5 T e r g i t e s 8 and 9 w i t h p a l e b l o t c h e s o r c o m p l e t e l y d a r k . P a l e s p o t s on head. F r o n t a l p l a t e extends beyond the a n t e r i o r h a l f o f the l a t e r a l edges of the e y e s . . . . . 5. 5. T e r g i t e s 8 and 9 w i t h p a l e b l o t c h e s o r c o m p l e t e l y d a r k . L a r g e p a l e spot.between the bases of the antennae and a n t e r i o r m a r g i n of the head sp. 6 T e r g i t e s 8 and 9 dark. Four p a l e s p o t s on the a n t e r i o r and l a t e r a l margins of the f r o n t a l p l a t e s p . 7 Unknown; H e p t a q e n i a s o l i t a r i a IYlcD HEPTAGENIA ELEGANTULA (EATON) H e p t a q e n i a e l e q a n t u l a ( E a t o n ) , Needham, 1935, The B i o l o g y o f Way-f l i e s , 345 ( B i b l i o g r a p h y ) A d u l t ; A y e l l o w i s h s p e c i e s ; t h o r a c i c notum p a l e y e l l o w i s h ; a median r e d d i s h brown s t r i p e on mesonotum; a b l a c k s t r e a k above m i d d l e and h i n d coxae and a b l a c k dot p o s t e r i o r to h i n d coxae; wings h y a l i n e ; -89-c o s t a l margin of f o r e w i n g may be t i n g e d w i t h p a l e lemon y e l l o w , w i t h g r e e n i s h or b i s t r e - g r e y ; v e n a t i o n f i n e , b l a c k , e x c e p t f o r y e l l o w amber b a s a l h a l v e s of Sc and R; humeral c r o s s v e i n and c o s t a l c r o s s -v e i n s t h i c k e r ; a w e l l marked b l a c k . b u l l a ; abdominal t e r g i t e s p a l e ; t e r g i t e s 2-7 s e m i - h y a l i n e w i t h smoky grey or b r o w n i s h p o s t e r i o r m a r g i n s ; t e r g i t e s 8-10 opaque, t i n g e d w i t h p i n k ; s t e r n i t e s p a l e y e l l o w i s h ; g e n i t a l i a of e l e g a n t u l a t y p e . Nymph; Pronotum w i d e s t a t the a n t e r i o r m a r g i n ; pronotum w i t h a wide p a l e median s t r e a k and p a l e l a t e r a l a r e a s ; c l a w s l a c k i n g p e c t i n -a t i o n s ; no o b l i q u e dark l i n e s on abdominal t e r g i t e s ; p a l e submedian s t r e a k s on t e r g i t e s 8 and 9 c o a e l e s c e t o form a l a r g e p a l e b l o t c h on each; no p o s t e r o - l a t e r a l s p i n e s on t e r g i t e s 6 to 8; f i l a m e n t o u s p o r t i o n of 7 t h p a i r of g i l l s p r e s e n t . D i s t r i b u t i o n : C o l o r a d o , Nebraska, Kansas, Montana, Utah, B r i t i s h C o l u m b i a . No specimens of t h i s s p e c i e s were examined. HEPTAGENIA 5IMPLIC0IDES fflcDUNNQUGH H e p t a q e n i a s i m p l i c o i d e s McDunnough, Needham, 1935, The B i o l o g y of M a y f l i e s , 361 ( B i b l i o g r a p h y ) A d u l t : A p a l e y e l l o w i s h s p e c i e s ; . t h o r a x p a l e creamy to y e l l o w i s h w h i t e ; wings h y a l i n e ; v e n a t i o n p a l e ; b a s a l c o s t a l c r o s s v e i n s few i n number, a l m o s t i n v i s i b l e ; abdominal t e r g i t e s creamy w h i t e t o p a l e y e l l o w i s h , 2-6 s e m i - h y a l i n e , 7-10 opaque, w i t h no s e m i - t r a n s l u c e n t p a t c h e s o r -90-dark m a r k i n g s ; t r a c h e a e on t e r g i t e s o u t l i n e d i n p a l e g r e y ; g e n i t a l i a o f s i m p l i c o i d e s t y p e ; median s p i n e s on penes not l o n g , v e r y s l i g h t l y t w i s t e d a t base o n l y , no l a t e r a l s p i n e s near m a r g i n . Nymph: Head of normal s i g e , w i d t h no more t h a n pronotum, and head and t h o r a x t o g e t h e r no more than 3/4 as l o n g as the abdomen; no dark s p o t s on f r o n t a l margin of head; pronotum w i d e s t a t or near the m i d d l e ; femora l a r g e l y brown, w i t h p a l e b a s a l and d i s t a l s p o t s and a p a l e median g i g z a g band; t a r s u s w h o l l y dark brown; c l a w s w i t h p e c t i n a t i o n s ; abdominal t e r g i t e s w i t h p a l e submedian m a r k i n g s o b s c u r e d ; t e r g i t e s 8-10 l a r g e l y dark; s p i n e s on p o s t e r o - l a t e r a l . a n g l e s of t e r g i t e 8, and perhaps a l s o on 6 and 7; f i l a m e n t o u s p o r t i o n of 7 t h p a i r of g i l l s w a n t i n g . D i s t r i b u t i o n ; A l b e r t a , Washington, B r i t i s h Columbia No specimens of t h i s s p e c i e s were examined. HEPTAGENIA SOLITARIA fflcDUNNQUGH H e p t a q e n i a s o l i t a r i a fflcDunnough, Needham, 1935, The B i o l o g y of fflayflies, 361 ( B i b l i o g r a p h y ) A d u l t : A brown s p e c i e s ; t h o r a c i c notum brown w i t h a deeper brown m i d d o r s a l s t r i p e , p a r t i c u l a r l y e v i d e n t on mesonotum; s h o r t b l a c k s t r e a k s j u s t above bases of m i d d l e and h i n d coxae, and above t h e s e , o t h e r b l a c k s t r e a k s i n l i n e w i t h wing r o o t s ; t h e s e s t r e a k s may be o b s c u r e d ; wings h y a l i n e ; v e n a t i o n f i n e brown, e x c e p t f o r b a s a l h a l v e s of Sc and R which a r e . t h i c k e n e d and p a l e y e l l o w i s h ; c o s t a l margin t i n g e d w i t h p a l e lemon y e l l o w ; c r o s s v e i n s t h i c k e r than l o n g i t u d i n a l s ; abdominal - 9 1 -t e r g i t e s v e r y p a l e b r o w n i s h ; t e r g i t e s 2-7 w i t h a broad dark p u r p l i s h brown median s t r i p e e n c l o s i n g a narrow p a l e m i d - d o r s a l l i n e ; p o s t e r i o r margin dark p u r p l i s h brown w i t h broad submedian bands e x t e n d i n g f o r w a r d from t h i s , but not a t t a i n i n g the a n t e r i o r m a r g i n ; t h e s e m a r k i n g s may be o b s c u r e d and form a dark s h a d i n g , or the p a l e submedian markings from a n t e r i o r margin may be l u n a t e ; t e r g i t e s 8-10 opaque, l i g h t r e d d i s h brown; s t e r n i t e s p a l e r , no ruddy t i n g e ; g e n i t a l i a o f p u l l a t y p e ( f i g . 3 ) ; upper p a i r of median s p i n e s s m a l l e r than lower ones. Nymph; Unknown D i s t r i b u t i o n : Montana, C o l o r a d o , B r i t i s h C olumbia No specimens o f t h i s s p e c i e s were examined. H e p t a q e n i a s p. 1 A d u l t ; Thorax l i g h t brown; a p u r p l i s h p a t c h a n t e r i o r to each m e s o t h o r a c i c wing base; f o r e l e g s l i g h t brown; o t h e r l e g s y e l l o w ; abdominal t e r g i t e s p a l e brown w i t h a p u r p l i s h t i n g e ; t e r g i t e s 7-10 dark p u r p l i s h brown, s t e r n i t e p i n k i s h ; t a i l s y e l l o w ; g e n i t a l i a w i t h penes e l o n g a t e , t u b e l i k e , each w i t h two l a t e r a l s h arp s h o r t s p i n e s from base of second d i v i s i o n . Nymph: Unknown D i s t r i b u t i o n ; B r i t i s h Columbia M a t e r i a l Examined; 1 Female, B r i t i s h C o l u m b i a : Q u e s n e l , V I I I . 2 . 4 8 (G.3. S p e n c e r ) 1 Female, B r i t i s h C o l u m b i a : Q u e s n e l , V I I I . 1 3 . 4 8 (G.3. Spencer 2 M a l e s , B r i t i s h C o l u m b i a : Cowichan Lake, VI.12.35 ( J . L . McHugh) 1 ?, B r i t i s h C o l u m b i a : Nanaimo, VI.11.35 ( 3 . L . McHugh) -92-H e p t a q e n i a sp, 2 A d u l t : Very s i m i l a r t o H e p t a q e n i a s p . 1; t h o r a x and abdominal t e r g i t e s brown, l a c k i n g the p u r p l i s h t i n g e ; p a l e a r e a on p o s t e r o - l a t e r a l a n g l e s o f t e r g i t e s ; s t e r n i t e s p a l e , w i t h dark g a n g l i o n i c m a r k i n g s ; a l l l e g s and t a i l s p a l e ; 2nd c u b i t a l i n t e r c a l a r y bends f o r w a r d b a s a l l y toward 1 s t c u b i t a l i n t e r c a l a r y ; s h o r t s p i n e s on penes w a n t i n g . Nymph: Unknown D i s t r i b u t i o n : B r i t i s h Columbia m a t e r i a l Examined: 1 Wale, B r i t i s h C o l u m b i a : Q u e s n e l , V I I I . 3 . 4 8 , ( G . J . S p e n c e r ) 1 Male, B r i t i s h C o l u m b i a : L y t t o n , V I I I . 2 3 . 3 1 ( G . J . S p e n c e r ) 3 t e n e r a l a d u l t s t a k e n a t L y t t o n , B r i t i s h Columbia on VII.12.31 and one on V I I I . 2 3 . 3 1 , by G.J. Spencer a r e p r o b a b l y o f t h i s s p e c i e s . H e p t a q e n i a s p. 3 A d u l t : ( F e m a l e ) Very s i m i l a r to H e p t a q e n i a sp. 2, but p a l e m a r k i n g s on the abdominal t e r g i t e s c o n s i s t o f a t h i n median l i n e . f l a n k e d on each t e r g i t e by 2 l i g h t d o t s ; no g a n g l i o n i c m a r k i n g s ; c r o s s v e i n s on wings more numerous. Nymph: Unknown D i s t r i b u t i o n : B r i t i s h Columbia m a t e r i a l Examined: 1 Female, B r i t i s h C o l u m b i a : A u s t r a l i a n , V I I I . 1 5 . 4 8 ( G . J . Spencer) -93-H e p t a q e n i a sp. 4 A d u l t : (fflale) S i m i l a r t o H e p t a q e n i a sp. 3, but no p a l e a r e a s on t e r g i t e s ; a v e r y dark brown s p e c i e s ; p a l e s p o t on m i d l i n e of mesonotum. Nymph: Unknown D i s t r i b u t i o n : B r i t i s h Columbia m a t e r i a l Examired: 1 Fflale, B r i t i s h C o l u m b i a : C h i l c o t i n , IX.22.62 (G.G.E. Scudder) H e p t a q e n i a sp. 5 A d u l t : Unknown Nymph: F r o n t a l p l a t e does not extend beyond the eyes; no p a l e s p o t s on head; pronotum w i d e s t a t a n t e r i o r m a r g i n ; c l a w s l a c k i n g i n p e c t -i n a t i o n s ; abdominal t e r g i t e s w i t h no p a l e submedian s t r e a k s ; t e r g i t e s 8-10 or 9-10 c o m p l e t e l y p a l e ; f i l a m e n t o u s p o r t i o n o f 7 t h p a i r of g i l l s p r e s e n t ; no abdominal s p i n e s on t e r g i t e 8. D i s t r i b u t i o n : B r i t i s h Columbia m a t e r i a l Examined -: 2 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) 11.15.60 . (N.O. F i l m e r ) H e p t a q e n i a sp. 6 A d u l t : Unknown Nymph: F r o n t a l p l a t e of head e x t e n d s beyond the a n t e r i o r h a l f o f the l a t e r a l edges of the eyes; l a r g e p a l e s p o t between the bases o f the antennae and the a n t e r i o r margin of the head; pronotum w i d e s t a t the -94-a n t e r i o r m a r g i n ; c l a w s l a c k i n g i n p e c t i n a t i o n s ; abdominal t e r g i t e s w i t h no p a l e submedian s t r e a k s ; t e r g i t e s 8 and 9 may have p a l e b l o t c h e s , o r may be c o m p l e t e l y dark; no abdominal s p i n e s on t e r g i t e 8; f i l a m e n t o u s p o r t i o n o f 7 t h p a i r o f g i l l s p r e s e n t . D i s t r i b u t i o n : B r i t i s h C olumbia M a t e r i a l Examined; 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) 11.15.60 ( N . J . F i l m e r ) H e p t a q e n i a sp. 7 A d u l t : Unknown Nymph: F r o n t a l p l a t e o f head extends beyond the a n t e r i o r h a l f of t h e l a t e r a l edges o f the e y e s , f o u r p a l e s p o t s on the a n t e r i o r and l a t e r a l m a rgins o f the f r o n t a l p l a t e ; pronotum w i d e s t a t t h e a n t e r i o r m a r g i n ; c l a w s l a c k i n g i n p e c t i n a t i o n s ; abdominal t e r g i t e s w i t h 2 p a l e s p o t s l a t e r a l l y on each; t e r g i t e s w i t h no submedian p a l e s t r e a k s ; t e r g i t e s 8 and 9 dark; no abdominal s p i n e s on t e r g i t e 8; f i l a m e n t o u s p o r t i o n of 7 t h p a i r o f g i l l s p r e s e n t . E c o l o g y : Specimens of t h i s s p e c i e s were t a k e n from the m i d d l e and edge of t h e A l o u e t t e R i v e r , from stream beds v a r y i n g from s i l t , t h r o u g h sand, mud, g r a v e l , r o c k s , b o u l d e r s , t o b e d r o c k , a t a depth of 1 to 2 f e e t . The m a j o r i t y were t a k e n from the edges of the r i v e r . The c u r r e n t was q u i e t o r r i p p l e y i n t h e s e l o c a t i o n s . A l l were t a k e n from J u l y 28 to August 11, 1959. -95-D i s t r i b u t i o n : B r i t i s h C olumbia m a t e r i a l Examined: 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) VII.28.59 (N.j\". F i l m e r ) ; 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) V I I I . 1 1 . 5 9 ( N . J . F i l m e r ) ; 5 Nymphs, B r i t i s h C o l u m b i a : N i c o l a Creek H e p t a g e n i a sp. 8 A d u l t : Unknown Nymph: F r o n t a l p l a t e o f head e x t e n d s beyond the eyes; t h r e e p a l e s p o t s between the eyes and the a n t e n n a l b a s e s ; pronotum w i d e s t near the m i d d l e ; femora brown w i t h the b a s a l p a r t p a l e and b e a r i n g a p a l e z i g z a g mark; t a r s u s brown w i t h m i d d l e p a r t p a l e ; c l a w s w i t h o u t p e c t -i n a t i o n s ; abdominal t e r g i t e s brown; t e r g i t e 4 w i t h a p a l e o b l o n g p a t c h on i t s p o s t e r i o r m a r g i n ; t e r g i t e 8 l a r g e l y p a l e ; no abdominal s p i n e s on t e r g i t e 8; f i l a m e n t o u s p o r t i o n o f 7 t h p a i r of g i l l s w a n t i n g . D i s t r i b u t i o n : B r i t i s h Columbia m a t e r i a l Examined: 43 Nymphs, B r i t i s h C o l u m b i a : N i c o l a Creek. GENUS RITHRDGENA EATON R i t h r o q e n a , Needham, 1935, The B i o l o g y of m a y f l i e s , 369 ( B i b l i o g r a p h y ) A d u l t : medium to l a r g e , dark brown or r e d d i s h brown m a y f l i e s ; eyes of male l a r g e , u s u a l l y c o n t i g u o u s a p i c a l l y ; p o s t e r i o r margin o f pronotum d e e p l y e x c a v a t e d m e d i a l l y ; f o r e l e g of male l o n g e r than body, o f f e m a l e , s l i g h t l y l e s s than or e q u a l t o l e n g t h o f body; f o r e femur of male 3/4 the l e n g t h of the t i b i a , which i s 3/4 the l e n g t h of the t a r s u s ; b a s a l f o r e t a r s a l j o i n t l / 6 to l / 4 the l e n g t h o f the 2nd j o i n t ; f o r e femur o f f e m a l e 3/4 the l e n g t h of the t i b i a , which i s about t w i c e as l o n g as the t a r s u s ; b a s a l f o r e t a r s a l j o i n t l / 2 the l e n g t h o f the 2nd j o i n t ; i n h i n d l e g o f both s e x e s , t i b i a 1/4 the l e n g t h of the femur; t a r s u s l / 2 or l e s s t h a n 1/2 the l e n g t h o f the t i b i a ; a l l c l a w s d i s s i m i l a r ; t y p i c a l H e p t a g e i n i n e wing v e n a t i o n ; s t i g m a t i c c r o s s v e i n s anastomosed and s l a n t e d ; b a s a l c o s t a l and s u b c o s t a l c r o s s v e i n s weak; Of o f Rs of h i n d wing p r e s e n t ; second f o r k o f Rs u s u a l l y a r i s e s basad of f i r s t f o r k ; a p i c a l margin of f o r c e p s base of male u s u a l l y s l i g h t l y e x c a v a t e d m e d i a l l y , f l a n k e d by two s l i g h t l y rounded p r o j e c t i o n s ; f o r c e p s 4 - j o i n t e d , 2nd j o i n t l o n g and s l e n d e r ; penes u s u a l l y r o d -shaped, s e p a r a t e d v e r y near t h e base; s p i n e s u s u a l l y p r e s e n t on penes; s u b a n a l p l a t e o f female w e l l - d e v e l o p e d , a p i c a l margin- e n t i r e , u s u a l l y o b t u s e l y rounded. Nymph: Head f l a t t e n e d and s l i g h t l y d e f l e x e d ; f r o n t a l margin e n t i r e and s l i g h t l y e m a r g i nate m e d i a l l y ; head w i d e s t a t l e v e l o f the a n t e r i o r p o r t i o n o f the eyes; labrum 4 t i m e s as wide as l o n g , a n t e r i o r margin s l i g h t l y e m a r g i nate m e d i a l l y ; o u t e r c a n i n e s o f m a n d i b l e s a t l e a s t t w i c e the l e n g t h o f the i n n e r ones, s l a n t i n g o b l i q u e l y i n w a r d s , and s h a r p l y t r u n c a t e a t t h e i r o u t e r bases o p p o s i t e the i n n e r c a n i n e s ; l a c i n i a r e p l a c e d by a row of f i n e l y p e c t i n a t e s p i n e s ; crown of g a l e a - l a c i n i a b e a r i n g a s e r i e s o f p e c t i n a t e s p i n e s ; m a x i l l a r y p a l p i 2 - j o i n t e d , f i r s t j o i n t d i l a t e d b r o a d l y near t h e base, 2nd j o i n t s t o u t l y c l a v a t e , o b l i q u e a p i c a l l y ^ s h o r t e r than 4 t i m e s the l e n g t h o f the g a l e a - l a c i n i a , b e a r i n g many p a r a l l e l s e r i e s of p e c t i n a t e s p i n e s ; g l o s s a e of l a b i u m c o n i c a l , w i d e l y s e p a r a t e d a t base, u s u a l l y s l i g h t l y d i v e r g e n t a p i c a l l y ; -97-l a t e r a l margins o f pronotum f l a r e s l i g h t l y near a n t e r i o r margin; p o s t e r i o r margin e x c a v a t e d m e d i a l l y ; femur f l a t t e n e d , upper s u r f a c e and m a rgins b e a r i n g , many minute s p i n e - l i k e p r o c e s s e s , t h o s e on p o s t e r i o r margin l o n g e r ; femur s u b e q u a l t o or s l i g h t l y l o n g e r t h a n t i b i a ; t i b i a u s u a l l y w i t h a few s h o r t s p i n e s on median p o r t i o n o f upper s u r f a c e and a l o n g m a r g i n s ; t i b i a more th a n t w i c e the l e n g t h o f the t a r s u s ; c l a w s w i t h a s i n g l e s t o u t s p i n e l / 3 the d i s t a n c e from the base on the i n n e r margin and 2 or 3 s m a l l e r p e c t i n a t i o n s l a t e r a l l y near apex; abdominal t e r g i t e s each b e a r i n g a s h o r t a n t e r i o r and a b l u n t p o s t e r i o r s p i n e - l i k e p r o c e s s l a t e r a l l y near bases o f g i l l s ; g i l l s on segment 1-7, c o n s i s t i n g o f a l a m e l l a t e \"and a f i b r i l l a r p o r t i o n ; f i b r i l l a r p o r t i o n s d o r s a l , may be w a n t i n g on segment 7; a n t e r i o r l o b e of 1 s t and p o s t e r i o r l o b e of 7 t h p a i r s of g i l l s e n l a r g e d and e l o n g a t e d , meeting beneath the body; o t h e r g i l l s o v a l , each o v e r l a p p i n g t h e one b e h i n d i t , f o r m i n g a \" s u c k e r d i s c \" ; l a t e r a l m a r g ins of l a m e l l a e not t h i c k e n e d and bear no f i n g e r l i k e p r o j e c t i o n ; 7 t h l a m e l l a e always show t r a c h e a e w i t h l a t e r a l b r a n c h e s ; t h r e e t a i l s , m i d d l e t a i l f r i n g e d w i t h f i n e h a i r s on each s i d e , e x c e p t i n b a s a l t h i r d ; o u t e r t a i l s f r i n g e d i n a p i c a l 2/3 on i n n e r margin o n l y . Genotype: R i t h r o q e n a s e m i c o l o r a t a ( i n B a e t i s ) C u r t i s RITHROGENA Key To A d u l t s 1. Brunnea type o f g e n i t a l i a ( f i g . ^ ) 2. Not t h i s t y p e of g e n i t a l i a 4. 2. F i v e t o s i x s m a l l a p i c a l v e n t r a l s p i n e s m o r r i s o n i Banks -98-No prominent s p i n e s on i n n e r a p i c a l margin of penes.. 3. 3. S m a l l sharp s p i n e p r e s e n t on . l a t e r o - a p i c a l margin cn each d i v i s i o n o f penes..... v i r i l i s IticD No s m a l l sharp s p i n e p r e s e n t on l a t e r o - a p i c a l margin o f penes... d o d d s i McD 4. G e n i t a l i a o f r o b u s t a t y p e ( f i g . 3 ) . No marks on femur. S t r o n g l a t e r a l s p i n e p r e s e n t on each d i v i s i o n o f penes near base,,, r o b u s t a Dodds G e n i t a l i a o f j e j u n a ( f i g . 3) t y p e . S t r e a k on femur. No l a t e r a l s p i n e s on penes, o r s p i n e - b e a r i n g p r o c e s s . . . . . j e j u n a Eaton KeyTo Nymphs 1. G i l l s c o l o u r l e s s 2. G i l l s , r o s e or t i n g e d w i t h p u r p l i s h i n the d o r s a l h a l f . 5. 2. Each g i l l w i t h a s e t o s e r i d g e on the v e n t r a l s i d e 3. No s e t o s e r i d g e on the v e n t r a l s i d e of g i l l s 4. 3. Labrum w i t h a s l i g h t i n d e n t a t i o n i n the m i d l i n e . T r a c h e a t i o n i n the p r o x i m a l h a l f of g i l l s r o b u s t a Dodds Labrum w i t h no i n d e n t a t i o n i n the m i d l i n e . No t r a c h e a t i o n v i s i b l e i n g i l l s sp. 1 4. I n t e r m e d i a t e p a i r s o f g i l l s each bear a rounded, e a r - l i k e e r e c t d o r s a l l o b e .sp. 2 No e r e c t d o r s a l l o b e on g i l l s s p . 3 5. T e r g i t e s red-brown - . m o r r i s o n i Banks T e r g i t e s not red-brown 6. 6. I n t e r m e d i a t e p a i r s o f g i l l s each bear a rounded, e a r - l i k e e r e c t d o r s a l l o b e . T e r g i t e s green brown. G i l l s b r i g h t r o s e p i n k d o d d s i flflcD. No e r e c t d o r s a l l o b e s on g i l l s . T e r g i t e s brown. G i l l s t i n g e d -99-w i t h p u r p l i s h i n the d o r s a l h a l f v i r i l i s IYlcD Unknown: R i t h r o q e n a .je.juna Eaton RITHROGENA DODDS I McDUNNOUGH R i t h r o q e n a d o d d s i McDunnough, Needham, 1935, The B i o l o g y of M a y f l i e s , 376 ( B i b l i o g r a p h y ) A d u l t : A brown s p e c i e s ; l e g s dark umber-brown; femora w i t h a dark l o n g i t u d i n a l s t r e a k i n b a s a l h a l v e s , e n t i r e femur may appear shaded w i t h b l a c k ; wings h y a l i n e ; v e n a t i o n - f i n e , dark brawn; b a s a l c o s t a l c r o s s v e i n s o b s o l e s c e n t : abdominal t e r g i t e s brown, i n t e r s e g m e n t a l a r e a s p a l e r ; l a t e r o - a p i c a l a n g l e s of t e r g i t e s rounded, w i t h no s m a l l sharp s p i n e ; s t e r n i t e s d u l l y e l l o w i s h brown; g e n i t a l i a of brunnea t y p e ; penes a l m o s t s t r a i g h t , l o n g and s l e n d e r , s l i g h t l y d i v e r g e n t but n ot o u t c u r v e d o r t r u n c a t e a p i c a l l y ; eadh d i v i s i o n b road a t apex; s t r o n g l a t e r a l s p i n e p r e s e n t on each d i v i s i o n o f penes, near base, and a v e n t r a l s p i n e , near i n n e r m a r g i n , on each d i v i s i o n i n c e n t r a l p o r t i o n ; l a t e r o - a p i c a l s p i n e s on penes m i n u t e . Nymph: Abdominal t e r g i t e s green-brown; g i l l s b r i g h t r o s e - p i n k i n c o l o u r ; i n t e r m e d i a t e p a i r s o f g i l l s each bear a rounded, e a r - l i k e e r e c t d o r s a l l o b e . D i s t r i b u t i o n ' : B r i t i s h C olumbia No specimens o f t h i s s p e c i e s were examined. -100-RITHRQGENA 3E3UNA EATON R i t h r o q e n a j e j u n a E a t o n , Needham, 1935, The B i o l o g y o f M a y f l i e s , 380 ( B i b l i o g r a p h y ) A d u l t : A dark brown s p e c i e s ; l e g s s o o t y brown; femora each w i t h a b l a c k l o n g i t u d i n a l s t r e a k , b e g i n n i n g near base and t a p e r e d a t each end; wings h y a l i n e ; f a i n t g r e y i s h t i n t ; v e n a t i o n v e r y dark brown; many c o s t a l c r o s s v e i n s anastomosed; abdominal t e r g i t e s 2-5 t r a n s l u c e n t burnt-umber brown; p o s t e r i o r margins d a r k e r ; s t e r n i t e s p a l e r ; a p i c a l t e r g i t e s opaque; g e n i t a l i a of j e j u n a t y p e ; penes s t r o n g l y o u t c u r v e d a t t i p s ; penes d i s t i n c t l y narrowed a p i c a l l y ; no s m a l l s p i n e s a p i c a l l y on d i v i s i o n s ; no l a t e r a l s p i n e o r s p i n e b e a r i n g p r o c e s s on penes; a p i c a l margin o f f o r c e p s base p r o j e c t i n g backward w i t h a d i s t i n c t rounded median e x c a v a t i o n . Nymph: Unknown D i s t r i b u t i o n : Quebec, B r i t i s h Columbia No specimens of t h i s s p e c i e s were examined. RITHROGENA IY10RRIS0NI BANKS R i t h r o q e n a m o r r i s o n i Banks, Needham, 1935, The B i o l o g y o f M a y f l i e s , 381 ( B i b l i o g r a p h y ) A d u l t : A dark brown s p e c i e s ; f o r e l e g s brown, o t h e r l e g s p a l e r ; femora of l a t t e r w i t h dark brown s t r e a k s ; wings h y a l i n e ; v e n a t i o n f i n e , brown; humeral c r o s s v e i n s deep b l a c k i s h : s t i g m a t i c a r e a smoky; c r o s s -v e i n s m o s t l y anastomosed or f o r k i n g ; a b d o m i n a l t e r g i t e s d u l l brown, a p i c a l ones d a r k e r ; p o s t e r i o r margins d a r k e r ; l a t e r a l m a r gins p a l e y e l l o w i s h ; s t e r n i t e s d u l l y e l l o w i s h ; g e n i t a l i a o f brunnea t y p e ; penes -101-r e l a t i v e l y l o n g and s l e n d e r , s t r o n g l y d i v e r g e n t a p i c a l l y , narrowed a t apex w i t h l a t e r a l a p i c a l margins rounded; each d i v i s i o n w i t h a s t r o n g l a t e r a l s p i n e and a s m a l l d i s t i n c t v e n t r a l s p i n e near i n n e r m argin i n c e n t r a l p o r t i o n ; and 5-6 s m a l l a p i c a l v e n t r a l s p i n e s . Nymph: A red-brown s p e c i e s ; l e g s p a l e ; o u t e r s u r f a c e o f femora brown, each w i t h a l a r g e median dark brown s p o t and b l a c k apex; abdominal t e r g i t e s 8-10 w i t h p a l e submedian s p o t s ; g i l l s sometimes r o s e - t i n t e d . D i s t r i b u t i o n : B r i t i s h C o l umbia No specimens of t h i s s p e c i e s were examined. RITHROGENA ROBUSTA DODDS R i t h r o g e n a r o b u s t a Dodds, Needham, 1935, The B i o l o g y of M a y f l i e s , 382 ( B i b l i o g r a p h y ) A d u l t : A l a r g e dark brown s p e c i e s ; f o r e l e g s dark brown, o t h e r l e g s s l i g h t l y p a l e r brown; no marks on femora a l t h o u g h the a p i c e s are d a r k e r brown; wings h y a l i n e ; not t i n t e d , e x c e p t i n s t i g m a t i c a r e a , which i s b r o w n - t i n g e d ; v e n a t i o n dark brown; humeral c r o s s v e i n s l i g h t r e d -brown, p a l e at c o s t a l m a r g i n ; b a s a l c o s t a l and s u b c o s t a l c r o s s v e i n s p a l e and f a i n t ; s t i g m a t i c c o s t a l c r o s s v e i n s anastomosed; abdominal t e r g i t e s 2-7 s e m i - h y a l i n e , dark red-brown; l a t e r a l and p o s t e r i o r m argins and i n t e r s e g m e n t a l a r e a s p a l e y e l l o w i s h brown; each t e r g i t e w i t h a narrow p a l e r mid d o r s a l l i n e and p a l e h y a l i n e wedge-shaped submedian s t r e a k s near c e n t e r ; t e r g i t e s 8-10 opaque, a l m o s t b l a c k -brown; s t e r n i t e s p a l e red-brown w i t h g a n g l i o n i c a r e a s o u t l i n e d i n dark brown i n most segments; g a n g l i o n i c a r e a s b l a c k i s h i n a p i c a l segments; g e n i t a l i a o f r o b u s t a t y p e ; d i v i s i o n s of penes r e l a t i v e l y s h o r t and s t o u t , w i d e l y d i v e r g e n t a p i c a l l y , r o u n d l y t r u n c a t e a t t i p s ; -102-a s t r o n g l a t e r a l s p i n e - l i k e p r o c e s s i s p r e s e n t on each d i v i s i o n , the o u t e r s h o r t and s t o u t , and the l a r g e r on the i n n e r margin w i t h i t s t i p s l i g h t l y c u r v e d i n w a r d and the s m a l l e r one d i r e c t e d upuiard. Nymph: G i l l s c o l o u r l e s s , no e r e c t d o r s a l l o b e on g i l l s . D i s t r i b u t i o n : B r i t i s h Columbia No specimens of t h i s s p e c i e s were examined. RITHROGENA UIRIL I S McDUNNOUGH R i t h r o q e n a v i r i l i s McDunnough, Needham, 1935, The B i o l o g y of M a y f l i e s , 384 ( B i b l i o g r a p h y ) A d u l t : A l a r g e brown s p e c i e s ; f o r e l e g s deep smoky; o t h e r l e g s l i g h t e r brown; a l l femora w i t h a l o n g i t u d i n a l dark s t r e a k ; wings h y a l i n e ; c o s t a f a i n t l y a m b e r - t i n g e d ; v e n a t i o n f i n e , dark brown; s t i g m a t i c c r o s s v e i n s anastomosed; abdominal t e r g i t e s brown w i t h i r r e g u l a r p a l e r l a t e r a l m a r g i n s ; s t e r n i t e s brown, p o s t e r i o r s t e r n i t e s p a l e r ; g e n i t a l i a o f brunnea t y p e ; d i v i s i o n s of penes r e l a t i v e l y l o n g and s l e n d e r , not t r u n c a t e a p i c a l l y ; a s t r o n g l a t e r a l s p i n e p r e s e n t near base of each d i v i s i o n ; no p r ominent s p i n e on i n n e r a p i c a l m a r g i n s , but on each l a t e r a l a p i c a l margin i s a s m a l l sharp s p i n e . Nymph: T e r g i t e s brown; g i l l s t i n g e d w i t h p u r p l i s h i n the d o r s a l h a l f ; no e r e c t d o r s a l l o b e on g i l l s . D i s t r i b u t i o n : A l b e r t a , B r i t i s h Columbia No specimens of t h i s s p e c i e s were examined. R i t h r o q e n a s p. 1 A d u l t : Unknown: -103-IMymph: G i l l s c o l o u r l e s s ; f i r s t and l a s t g i l l s meeting beneath the body; each g i l l u/ith a s e t o s e r i d g e on the v e n t r a l s i d e ; no t r a c h e a t i o n v i s i b l e i n the g i l l s ; a s m a l l dark square on the 7 t h s t e r n i t e , labrum w i t h no i n d e n t a t i o n i n m i d l i n e . D i s t r i b u t i o n : B r i t i s h C olumbia M a t e r i a l Examined; 3 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) XI.26.59 ( N . J . F i l m e r ) 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) XI.8.59 ( N . J . F i l m e r ) R i t h r o o e n a s p . 2 A d u l t : Unknown Nymph: G i l l s c o l o u r l e s s ; no s e t o s e r i d g e on v e n t r a l s i d e o f g i l l s ; i n t e r m e d i a t e p a i r s of g i l l s each bear an e r e c t rounded e a r - l i k e l o b e ; f i r s t p a i r o f g i l l s meet beneath the body. D i s t r i b u t i o n : B r i t i s h C olumbia m a t e r i a l Examined: 10 Nymphs, B r i t i s h C o l u m b i a : Loon Creek, (H. L o r g ) ; 1 Nymph, B r i t i s h C o l u m b i a : Loon Creek H a t c h e r y Ponds, C l i n t o n , VI.16.56 (H. L o r z ) ; 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C. ) V.14.59, ( N . J . F i l m e r ) R i t h r o q e n a sp. 3 A d u l t : Unknown Nymph: A u n i c o l o u r e d brown s p e c i e s ; g i l l s p a l e ; no s e t o s e r i d g e on v e n t r a l s i d e of g i l l s ; no e r e c t d o r s a l l o b e on g i l l s ; no t r a c h e a t i o n -104-on g i l l s ; no i n d e n t a t i o n on m i d l i n e o f labr u m . D i s t r i b u t i o n : B r i t i s h C olumbia M a t e r i a l Examined: 2 Nymphs, B r i t i s h C o l u m b i a : Loon Creek, C l i n t o n , VI.16.56 (H. L o r z ) GENUS STENQNEMA TRAVER Stenonema, Needham, 1935, The B i o l o g y o f M a y f l i e s , 295 ( B i b l i o g r a p h y ) A d u l t : S m a l l t o moderate s i z e d m a y f l i e s ; eyes of male moderate s i z e , n o t c o n t i g u o u s a p i c a l l y ; p o s t e r i o r margin o f pronotum d e e p l y e x c a v a t e d m e d i a l l y ; f o r e l e g of male as l o n g o r s l i g h t l y l o n g e r than body; f o r e femur o f male 3/4 as l o n g as t i b i a , u/hich i s 3/4 as l o n g as the t a r s u s ; b a s a l f o r e t a r s a l j o i n t l / 3 t o l / 2 as l o n g as the second; f o r e femur o f female s u b e q u a l or s l i g h t l y s h o r t e r than t i b i a , which i s s l i g h t l y l o n g e r t h a n the t a r s u s ; i n h i n d l e g of both s e x e s , femur s u b e q u a l o r s l i g h t l y l o n g e r than t i b i a , which i s t w i c e as l o n g as the t a r s u s ; a l l c l a w s d i s s i m i l a r ; t y p i c a l Heptagenine wing v e n a t i o n ; b a s a l c o s t a l c r o s s v e i n s s t r o n g ; c r o s s v e i n s a t and below the b u l l a may be crowded; s t i g m a t i c c r o s s v e i n s s l a n t e d , not anastomosed, though a few may be f o r k e d ; c o s t a l c r o s s v e i n s and t h o s e a t b u l l a may be dark margined; Of of Rs o f h i n d margin p r e s e n t ; f o r c e p s 4 - j o i n t e d ; a p i c a l margin o f f o r c e p s base not de e p l y e x c a v a t e d ; penes more o r l e s s d i s t i n c t l y L-shaped; d i v i s i o n o f penes w i t h a p a i r of s t o u t median s p i n e s , may be s m a l l e r l a t e r a l and a p i c a l s p i n e s ; s u b a n a l p l a t e o f female w e l l d e v e l o p e d , e x t e n d i n g beyond 10th segment, i t s a p i c a l m argin e n t i r e , t r u n c a t e or v e r y s l i g h t l y e m a r g i n a t e i n m i d d l e a r e a . Nymph: F r o n t o f head may be s l i g h t l y e m a r g i n a t e ; i n n e r mandibulan c a n i n e about 7/8 as l o n g as the o u t e r one; upper crown o f g a l e a - l a c i n i a -105-b e a r s b o t h s p i n e s and h a i r s or a row of p e c t i n a t e s p i n e s ; m a x i l l a r y p a l p i 2 - j o i n t e d , second j o i n t s h o r t e r than 4 t i m e s the l e n g t h of the g a l e a - l a c i n i a ; c l a w s may or may not have p e c t i n a t i o n s ; g i l l s c o n s i s t o f a l a m e l l a t e and a f i b r i l l a r p o r t i o n ; f i b r i l l a r p o r t i o n v e n t r a l ; no f i n g e r l i k e p r o j e c t i o n s on g i l l l a m e l l a e ; g i l l s do not meet beneath the body; l a m e l l a t e p o r t i o n of g i l l s may be rounded, t r u n c a t e or p o i n t e d a t apex; g i l l s of -7th segment t h r e a d l i k e or s p i n e -l i k e ; t h i s g i l l may c o n t a i n a s i n g l e t r a c h e a w i t h no l a t e r a l branches or a s i n g l e v ' f o r k e d t r a c h e a , and may be f r i n g e d w i t h l o n g h a i r s or may have a few f i n e h a i r s a l o n g the m a r g i n ; s p i n e s on p o s t e r o - l a t e r a l a n g l e s of a p i c a l t e r g i t e s , and may or may not be p r e s e n t on m i d d l e t e r g i t e s : t a i l s t h r e e . Genotype: Stenonema t r i p u n c t a t u m ( i n H e p t o q e n i a ) Banks STEN0NEIY1A TER1Y11MATU1Y1 (UJALSH) Stenonema terminatum ( W a l s h ) , Needham, 1935, The B i o l o g y of M a y f l i e s , \ .Spieth and I d e , 1939, Can. E n t . 71:167 ( B i b l i o g r a p h y ) A d u l t : A l i g h t ruddy s p e c i e s ; head y e l l o w i s h ; notum r e d d i s h to dark o l i v e brown, f o r e femora y e l l o w i s h , w i t h i n d i s t i n c t m i d d l e and a p i c a l ruddy bands; b a s a l j o i n t of f o r e t a r s u s l e s s than l / 2 or l i t t l e more than l / 3 the l e n g t h of the second; s c u t e l l u m w h i t i s h a t t i p ; wings h y a l i n e ; l o n g i t u d i n a l v e i n s o f c o s t a l margin y e l l o w i s h , r e s t r e d -brown; b a s a l c o s t a l and s u b c o s t a l c r o s s v e i n s t h i c k e n e d e q u a l l y , not more i n the c e n t e r than e l s e w h e r e ; c r o s s v e i n s a t and below the b u l l a , i n 1 s t t h r e e s p a c e s , a r r a n g e d as 1,1,1 - 1,2,1 - 1,2,2 - or 1,2,3 - o r 2,2,2 - s t i g m a t i c a r e a s l i g h t l y c l o u d y , not d a r k - s t a i n e d ; h i n d wing -106-v e n a t i o n h y a l i n e ; not da r k - m a r g i n e d ; abdominal t e r g i t e s 1-6 h y a l i n e w h i t i s h , p o s t e r i o r margins n a r r o w l y or w i d e l y red-brown i n d o r s a l p o r t i o n s ; a n t e r i o r h a l f o f t e r g i t e 7 h y a l i n e w h i t i s h , p o s t e r i o r h a l f opaque red-brown; t e r g i t e s 8-10 opaque r e d brown; no s p i r a c u l a r d o t s ; s t e r n i t e s p a l e r ; g e n i t a l i a of p u l c h e l l u m type ( f i g . 3 ) ; t a i l s w h o l l y p a l e , not d a r k e r a t j o i n i n g s , o r . p u r p l i s h a t b a s a l j o i n i n g s and o t h e r s f a i n t l y , d a r k . Nymph: T e r g i t e 7 l a r g e l y d a r k ; 2 narrow p a l e submedian s t r e a k s and narrow p a l e l i n e n e x t t o p o s t e r i o r m a r g i n ; a dark l a t e r a l mark on each s i d e of s t e r n i t e 9; dark v e n t r a l markings on segments 8, 9, or 9 o n l y ; P o s t e r i o r l a t e r a l s p i n e s on segments 7-9 o n l y ; s p i n e on segment 8 l o n g e r than 9; dorsium o f abdomen w i t h a d i s t i n c t p a t t e r n o f p a l e and dark a r e a s ; abdominal segments w i t h o u t dark c o n s p i c u o u s p o s t e r i o r bands d o r s a l l y and v e n t r a l l y ; g i l l s on segments 1-6 t r u n c a t e a t apex; 7 t h g i l l w i t h o u t a t r a c h e a ; c l a w s not toothed.. D i s t r i b u t i o n : Idaho, M a n i t o b a , B r i t i s h Columbia No specimens o f t h i s ' s p e c i e s were examined. SUBFAMILY METRETOPODINAE A d u l t : Eyes of male not t u r b i n a t e ; eyes o f male e n t i r e , a h o r i z o n t a l l i n e on the s u r f a c e d i v i d i n g each i n t o two a r e a s ; t a r s i f i v e - j o i n t e d , the b a s a l j o i n t , e x c e p t i n the f o r e l e g of the male, c o m p l e t e l y f u s e d w i t h the t i b i a ; f i r s t t a r s a l j o i n t s of m i d d l e and h i n d l e g s as l o n g or s l i g h t l y l o n g e r than the second; femora of m i d d l e and h i n d leg's -107-l o n g e r t h a n the t i b i a e ; a l l clauis d i s s i m i l a r ; Of of f o r e w i n g and p o s t e r i o r branch of the IY1 n o r m a l , a t t a c h e d b a s a i l y ; c u b i t a l i n t e r -c a l a r i e s . 2-4 i n number, f r e e b a s a i l y , not f o r k i n g or s i n u a t e o r j o i n e d t o the h i n d margin by c r o s s v e i n s ; 1 s t a n a l v e i n ends i n h i n d m a r g i n ; c o s t a l a n g u l a t i o n o f h i n d wing v a r i a b l e , Of p r e s e n t ; f o r c e p s base r o u n d l y e x c a v a t e d i n h i n d m a r g i n ; f o r c e p s 4 - j o i n t e d ; second j o i n t l o n g e s t ; penes may be u n i t e d a t apex or d i v i d e d h a l f - w a y from base i n t o rod-shaped p o r t i o n s ; s u b a n a l p l a t e of f e m a l e v a r i a b l e ; t a i l s two. Nymph; Nymph not d e p r e s s e d ; eyes and/or antennae l a t e r a l , a n t e r o - l a t e r a l , o r a n t e r i o r ; no s e t a e on l a t e r o - l a t e r a l a n g l e s of head; no s e t a e on i n n e r s u r f a c e of f o r e l e g s ; no g i l l t u f t s on m a x i l l a e o r f o r e coxae; c l a w s o f f o r e - l e g b i f i d ; c l a w s o f m i d d l e and h i n d l e g s l o n g and s l e n d e r , about as l o n g as the s h o r t t i b i a ; g i l l s on segments 1-7, r a r e l y on 1-5; g i l l s d o r s a l and w i t h o u t a f r i n g e d m a r g i n ; o u t e r t a i l s f r i n g e d on i n n e r s i d e only,, o r t h e r e may be a few s h o r t h a i r s on the o u t e r s i d e . GENUS WETRETOPUS EATON M e t r e t o p u s , Needham, 1935, The B i o l o g y o f M a y f l i e s , 434 ( B i b l i o g r a p h y ) A d u l t ; \u00E2\u0080\u00A2 A medium s i z e d b r o w n i s h s p e c i e s ; f o r e femur o f male about l / 2 the l e n g t h of the t i b i a , which i s l / 3 the l e n g t h o f the t a r s u s ; 1 s t t a r s a l j o i n t s u b e q u a l t o the second; i n the f e m a l e , the femur and the t i b i a a r e s u b e q u a l ; the t i b i a i s about 3/4 t h e l e n g t h o f the t a r s u s ; 1 s t t a r s a l j o i n t about 1-1/3 t i m e s t he l e n g t h of the second; a l l c l a w s d i s s i m i l a r ; f o r e w i n g w i t h a s i n g l e p a i r of c u b i t a l i n t e r -^\u00E2\u0080\u00A2108-c a l a r i e s , the a n t e r i o r v e i n b e i n g the l o n g e s t ; s t i g m a t i c c r o s s v e i n s t e n d t o anastomose; c o s t a l a n g u l a t i o n of h i n d wing a c u t e ; IYI2 n o r m a l , f o r k e d near the base; f o r c e p s base r o u n d l y e x c a v a t e d i n a p i c a l m a r g i n ; f o r c e p s 4 - j o i n t e d , the f i r s t 2 j o i n t s more o r l e s s f u s e d ; penes d i v i d e d i n the a p i c a l h a l f i n t o two r o d - l i k e s t r u c t u r e s , each c u r v i n g outward s l i g h t l y , w i t h a rounded l o b e on the i n n e r a p i c a l m a r g i n ; s u b a n a l p l a t e of female o b t u s e ; t a i l s two, the median t a i l i s r e p r e s e n t e d by a p a r t l y segmented r u d i m e n t . Nymph: M a x i l l a r y p a l p i 2 - j o i n t e d ; b a s a l j o i n t o f l a b i a l p a l p l o n g e r and s t o u t e r than the a p i c a l j o i n t , s w o l l e n on i t s o u t e r m a r g i n ; a p i c a l j o i n t l o n g and t h i n , t h i c k e r on i t s i n n e r s i d e , rounded a p i c a l l y ; f emora about as l o n g as t i b i a e and t a r s i t o g e t h e r ; t a r s i l o n g e r than the t i b i a e ; c l a w s d i s s i m i l a r on f o r e l e g , s i m i l a r on o t h e r s ; g i l l s on segment 1-7, s i m i l a r i n form; a l l g i l l s s i n g l e . Genotype: M e t r e t o p u s n o r v e q i c u s Eaton METRETOPUS BOREALIS EATON M e t r e t o p u s b o r e a l i s E a t o n , Edmunds and A l l e n , 1957, Ann. E n t . Soc. Amer. 50 (4) : 320 ( B i b l i o g r a p h y ) A d u l t : Abdominal t e r g i t e s 1, 7-10 brown, m i d d l e t e r g i t e s t r a n s l u c e n t ; p o s t e r i o r margins of t e r g i t e s n a r r o w l y marked w i t h brown; each t e r g i t e w i t h a brown m i d - d o r s a l l i n e w i t h a dark s t r e a k p r o c e e d i n g f o r w a r d from i t i n each segment to form a t r i a n g l e w i t h the apex d i r e c t e d p o s t e r i o r l y ; t a i l s dark g r e y . Nymph: Unknown D i s t r i b u t i o n : B r i t i s h Columbia No specimens o f t h i s s p e c i e s were examined. *109-SUBFAIHILY BAETINAE A d u l t : Eyes of male d i v i d e d , upper p o r t i o n t u r b i n a t e , s e t on a c y l i n d r i c a l s t a l k w i t h f a c e t s on the upper f l a t t e n e d s u r f a c e o n l y ; f a c e t s o f t u r b i n a t e p o r t i o n l o n g e r than th o s e o f lower p o r t i o n ; f o r e t a r s i w i t h 5 j o i n t s , t h e b a s a l j o i n t v e r y s h o r t ; o t h e r t a r s i 4 - j o i n t e d , b a s a l j o i n t p a r t i a l l y f u s e d w i t h t i b i a ; a l l c l a w s d i s -s i m i l a r ; wing v e n a t i o n r e d u c e d ; Of of Rs and p o s t e r i o r b r a n c h of the ITl a r e det a c h e d b a s a i l y from t h e i r r e s p e c t i v e stems; 1 s t ana l \ . v e i n ends i n the h i n d m a r g i n ; b a s a l c o s t a l c r o s s v e i n s o f t e n w a n t i n g ; b e h i n d s u b c o s t a , o t h e r c r o s s v e i n s few i n number and u s u a l l y a r r a n g e d i n s e v e r a l or l e s s d e f i n i t e s e r i e s a c r o s s the wing; 2 l o n g c u b i t a l i n t e r c a l a r i e s p r e s e n t ; s h o r t , w e l l - d e v e l o p e d m a r g i n a l i n t e r c a l a r i e s o c c u r s i n g l y , o r i n p a i r s i n each i n t e r s p a c e between the main v e i n s o r t h e l o n g i n t e r c a l a r i e s ; h i n d wing r e d u c e d i n s i z e , much l o n g e r than wide, or w a n t i n g ; i f p r e s e n t , v e n a t i o n c o n s i s t s of 2 o r 3 l o n g i -t u d i n a l v e i n s and a few or no c r o s s v e i n s ; Of of h i n d wing a b s e n t ; c o s t a l a n g u l a t i o n v a r i a b l e ; i f absent o r g r e a t l y r e d u c e d , a n a l p o r t i o n o f f o r e w i n g g r e a t l y d e v e l o p e d ; t a i l s two; penes i n t e r n a l ; may be a s i n g l e or d i v i d e d \" p e n i s c o v e r \" between the b a s a l j o i n t s o f the f o r c e p s . Nymph: A s l e n d e r s t r e a m l i n e d s p e c i e s w i t h a downward f l e x e d head and l o n g s l e n d e r l e g s ; antennae l a t e r a l , a n t e r o - l a t e r a l , or a n t e r i o r ; a n t e r o - l a t e r a l a n g l e s o f the head w i t h o u t s e t a e ; f o r e l e g s w i t h o u t a dense row of s e t a e on the i n n e r s u r f a c e ; no g i l l t u f t s on m a x i l l a e -110-o r f o r e c o x a e ; no appendages on f o r e coxae; c l a w s s i m i l a r , s h a r p -p o i n t e d , and much s h o r t e r than the t i b i a e ; c l a w s of the m i d d l e and h i n d l e g s may be l o n g and s l e n d e r , and of the f o r e l e g s s h o r t ; p o s t e r o -l a t e r a l a n g l e s of the a p i c a l abdominal t e r g i t e s u s u a l l y not p r o l o n g e d i n t o f l a t t h i n l a t e r a l s p i n e s , but i f weakly so , the antennae a r e more th a n t w i c e the w i d t h of the head; g i l l s on segments 1-7, and r a r e l y on 1-5 o n l y ; g i l l s l a m e l l a t e , m a rgins e n t i r e ; g i l l s s i n g l e , a p i c a l ones may bear a minute v e n t r a l r e c u r v e d f l a p ; t a i l s 2 or 3, o u t e r ones w i t h a heavy f r i n g e of h a i r s on the i n n e r m a r g i n , and few o r none on the o u t e r ; m i d d l e t a i l , i f p r e s e n t , f r i n g e d on both s i d e s . SUBFAMILY BAETINAE Key To A d u l t s 1. H ind wings a b s e n t . 2. H i nd wings p r e s e n t 3. 2. M a r g i n a l i n t e r c a l a r i e s of f o r e w i n g o c c u r i n p a i r s . F i r s t j o i n t o f t h i r d t a r s u s s h o r t , e q u a l t o segments 2 and 3... P s e u d o c lo e o n n K l a p a l e k M a r g i n a l i n t e r c a l a r i e s of f o r e w i n g o c c u r s i n g l y . F i r s t j o i n t o f t h i r d t a r s u s l o n g , e q u a l t o segments 2 and 3 and 4 Neocloeon'- T r a v e r 3. Forewing u s u a l l y w i t h numerous c o s t a l c r o s s v e i n s b e f o r e the b u l l a . H i nd wings w i t h a moderate number of c r o s s v e i n s , a t l e a s t i n the c o s t a l r e g i o n C a l l i b a e t i s Eaton Forewing w i t h o u t c o s t a l c r o s s v e i n s b e f o r e the b u l l a . H i nd wings w i t h no c r o s s v e i n s , or w i t h v e r y few. 4. 4. M a r g i n a l i n t e r c a l a r i e s of f o r e w i n g o c c u r i n p a i r s . F i r s t j o i n t o f t h i r d t a r s u s s h o r t , e q u a l to segments 2 and 3. . . . B a e t i s Leach - I l l -m a r g i n a l i n t e r c a l a r i e s o f f o r e w i n g o c c u r s i n g l y . F i r s t j o i n t o f t h i r d t a r s u s l o n g , e q u a l t o segments 2 and 3 and 4. , C e n t r o p t i l u m Eaton Key To Nymphs 1. 3 t a i l s , m i d d l e t a i l may be s h o r t e r than 10th t e r g i t e . . 2. 2 t a i l s P s e u d o c l b e o n , i K l a p a l e k 2. M e t a t h o r a c i c wing pads absent .Neocld.eonn T r a v e r m e t a t h o r a c i c wing pads p r e s e n t , may be minute .3. 3. G i l l l a m e l l a e d o u b l e on abdominal segments 1-6 ( d o r s a l p o r t i o n o f t e n m erely a r e c u r v e d f l a p ) . T a i l s e q u a l 4. G i l l l a m e l l a e s i n g l e on a l l abdominal segments, m i d d l e t a i l s h o r t e r and weaker (may be s h o r t e r t h a n 10th t e r g i t e ) t h a n o u t e r ones B a e t i s Leach 4. Double p o r t i o n o f g i l l i s a f l a p on the v e n t r a l s u r f a c e , m a x i l l a r y p a l p s 2 j o i n t e d . D i s t a l j o i n t of l a b i a l p a l p c o n i c a l . , Claws t o o t h e d . . C a l l i b a e t i s Eaton Double p o r t i o n o f g i l l i s a f l a p on the d o r s a l s u r f a c e , m a x i l l a r y p a l p . 3 j o i n t e d . D i s t a l j o i n t o f l a b i a l p a l p d i l a t e d . Claws not t o o t h e d C e n t r o p t i l u m Eaton GENUS BAETIS LEACH B a e t i s , Needham, 1935, The B i o l o g y o f M a y f l i e s , 674 ( B i b l i o g r a p h y ) A d u l t : S m a l l b r o w n i s h m a y f l i e s ; t u r b i n a t e eyes of male s m a l l , moderate or l a r g e ; eyes of female not t u r b i n a t e , but s m a l l and remote; head o f female w i t h h i n d margin emarginate m e d i a l l y , w i t h a s l i g h t outward p r o l o n g a t i o n on each s i d e o f t h i s e m a r g i n a t i o n ; p r o t h o r a x s m a l l ; a s h o r t p r o t u b e r a n c e near the mi d d l e of the metanotum.; f o r e l e g of male -112-as l o n g as the body; femur 3/4 the l e n g t h of the t i b i a , which i s as l o n g as or s l i g h t l y s h o r t e r than the t a r s u s ; b a s a l t a r s a l j o i n t v e r y s h o r t ; h i n d femur and t i b i a s u b e q u a l , t i b i a l o n g e r t h a n the t a r s u s ; b a s a l t a r s a l j o i n t o f h i n d l e g not l o n g e r than 2nd and 3 r d j o i n t s t o g e t h e r ; m a r g i n a l i n t e r c a l a r i e s of f o r e w i n g o c c u r i n p a i r s ; c o s t a l c r o s s v e i n s w a n t i n g b e f o r e t h e b u l l a ; h i n d wing f a i r l y w e l l d e v e l o p e d ; c o s t a l p r o j e c t i o n u s u a l l y p r e s e n t , may be a c u t e or s l i g h t l y c u r v e d ; 2 or 3 l o n g i t u d i n a l v e i n s , t h e 3 r d , i f p r e s e n t , r a t h e r s h o r t ; no c r o s s v e i n s , or v e r y few; a bdominal t e r g i t e s of female u n i c o l o u r e d r e d d i s h or b r o w n i s h ; of male, 2-6 are u s u a l l y s e m i - h y a l i n e or h y a l i n e , p a l e t o o l i v a c e o u s t o deep brown; 2nd and 3 r d j o i n t s of f o r c e p s f u s e d ; g e n i t a l i a v a r i a b l e . Nymph; Labrum w i t h a d i s t i n c t narrow n o t c h i n the a p i c a l m a r g i n ; m a x i l l a r y p a l p 2 or 3 - j o i n t e d ; l a b i a l p a l p 3 - j o i n t e d , \u00E2\u0080\u00A2 t h e d i s t a l j o i n t rounded; m e t a t h o r a c i c wing pads p r e s e n t , may be m i n u t e ; c l a w s t o o t h e d on i n n e r m a r g i n ; g i l l s s i n g l e , on segments 1-7; g i l l s o b o v a t e , p i n n a t e l y b r a n c h e d , g i l l s on 6 and 7 may be narrow and l a n c e o l a t e ; u s u a l l y 3 t a i l s , t h e m i d d l e one s h o r t e r and weaker th a n the o t h e r s ; t h e r e may o n l y be 2 t a i l s , o r the t h i r d t a i l may be s h o r t e r than the 10th t e r g i t e . . Genotype: B a e t i s b i o c u l a t u s ( i n Ephemera) L i n n a e u s BAETIS Key To A d u l t s 1. C o s t a l p r o j e c t i o n of h i n d wing p r o m i n e n t , a c u t e 2. C o s t a l p r o j e c t i o n of h i n d wing w a n t i n g i n s i q n i f i c a n s lYlcD -113-H i nd wing w i t h 2 l o n g i t u d i n a l v e i n s o n l y , e q u a l i n l e n g t h . 3 r d v e i n w h o l l y w a n t i n g b i c a u d a t u s Dodds Hi n d wing w i t h 3 l o n g i t u d i n a l v e i n s . 3 r d v e i n may be s h o r t or weak... \u00E2\u0080\u00A2 .3. 2nd l o n g i t u d i n a l v e i n o f f o r e w i n g f o r k e d about l / 3 the d i s t a n c e from the base t o the margin p a r v u s Dodds 2nd l o n g i t u d i n a l v e i n o f f o r e w i n g not f o r k e d . . . . . 4. One i n t e r c a l a r y v e i n between v e i n s 2 and 3 of h i n d wing 5. No d e f i n i t e i n t e r c a l a r i e s on h i n d wing p e r s e c u t a IYlcD 3 r d v e i n o f h i n d w i n g e n d i n g near m i d d l e o f . h i n d m a r g i n . i n t e r m e d i u s Dodds 3 r d v e i n o f h i n d w i n g e n d i n g 2/3 a l o n g h i n d margin .jesmondensis IYlcD Key To Nymphs Two t a i l s o n l y ...2. Three t a i l s 3. D i s t i n c t p a l e 3-shaped mark on 1 s t femur, L-shaped on femora 2 and 3. T e r g i t e s 3, 4, and 7 d a r k e r than the o t h e r s '.bicaudatus Dodds No d i s t i n c t 3 or L-shaped marks on femora. T e r g i t e s 3, 4 and 7 not d a r k e r than the o t h e r s . . s p . 1 M i d d l e t a i l about l / 6 the l e n g t h of the o u t e r ones. 4 M i d d l e t a i l a t l e a s t - : l / 2 the l e n g t h of t h e o u t e r ones. 5 F i r s t femur w i t h a J-shaped p a l e mark. Second femur w i t h an L-shaped p a l e mark. A l l t e r g i t e s w i t h p a l e m a r k i n g s , t e r g i t e s 5-8 and 9 p a l e r than the o t h e r s . . . i n t e r m e d i u s - Dodds -114-No 3 b r - L - s h a p e d markings on the femora. T e r g i t e s m o s t l y w i t h -o u t p a l e m a r k i n g s . T e r g i t e s 5, 8 and 9 p a l e r than the o t h e r s , t h o s e on segments 5 and 8 each w i t h two s u b m e d i a l d o t s . . . s p . 2 5. M i d d l e t a i l 3/4 t o 5/6 the l e n g t h of t h e o u t e r ones .......6. M i d d l e t a i l about 1/2 the l e n g t h of the o u t e r ones 9. 6. M i d d l e t a i l a t l e a s t 5/6 the l e n g t h of the o u t e r ones 7 M i d d l e t a i l 3/4 t o 5/6 the l e n g t h of the o u t e r ones..parvus Dodds 7. T e r g i t e s p a t t e r n e d w i t h brown, some p a l e r t h a n o t h e r s . Two p a l e s u b l a t e r a l l i n e s on t e r g i t e s . Wing pads dark o r l i g h t 8. T e r g i t e s p a t t e r n e d w i t h brown, none l i g h t e r than o t h e r s . T e r g i t e s 8, 9, and 10 w i t h l a t e r a l dark l i n e s . Wing pads d a r k . . . s p . 4 8. T e r g i t e s p a t t e r n e d w i t h brown, t e r g i t e s 5, 6, 9 and 10 p a l e r than the o t h e r s . The p a t t e r n on t e r g i t e s 7 and 8 i s a dark t r i a n g l e , apex a n t e r i o r , w i t h a s p o t on each s i d e of the apex. A dark m e d i a l l i n e on t e r g i t e s 9 and 10. UJing pads l i g h t s p. 5 A l l t e r g i t e s brown, t h o s e on segments 8-10 p a l e r , w i t h l a t e r a l and m e d i a l dark bands.- Wing pads dark or l i g h t s p. 6 9. G i l l t r a c h e a t i o n not d i s t i n c t . G i l l s o f average s i z e . . . . . . . s p . 3 G i l l t r a c h e a t i o n d i s t i n c t . G i l l s l a r g e . . . . . . sp. 7 Unknown: B a e t i s i n s i q n i f r a n s McD B a e t i s p e r s e c u t a McD B a e t i s jesmondensis McD BAETIS BICAUDATUS DODDS B a e t i s b i c a u d a t u s Dodds, Needham, 1935, The B i o l o g y of M a y f l i e s , 682 ( B i b l i o g r a p h y ) -115-A d u l t : (Female) A u n i f o r m l y l i g h t brown s p e c i e s ; c o s t a l p r o j e c t i o n of h i n d wing prominent and a c u t e ; h i n d wing w i t h two l o n g i t u d i n a l v e i n s o n l y , which a r e a p p r o x i m a t e l y s u b e q u a l i n l e n g t h . Mymph; Abdominal t e r g i t e s 1 t o 10 p a l e w i t h dark m a r k i n g s , numbers 3, 4 and 7 d i s t i n c t l y d a r k e r than the o t h e r s ; a p p a r e n t l y o n l y two t a i l s , the m i d d l e t a i l b e i n g r e p r e s e n t e d by a minute s t u b . D i s t r i b u t i o n : C o l o r a d o , B r i t i s h C olumbia No specimens of t h i s s p e c i e s were examined. BAETIS INSIGNIFICAN5 lYicDUNNQUGH B a e t i s i n s i q n i f i c a n s lYIcDunnough, Needham, 1935, The B i o l o g y of m a y f l i e s , 692 ( B i b l i o g r a p h y ) A d u l t : T u r b i n a t e eyes s m a l l , b r i g h t r e d ; t h o r a x deep brown w i t h a n t e r i o r p r o j e c t i o n of metanotum p a l e c r e a m - c o l o u r e d ; a l l femora t i n g e d w i t h smoky brown; f o r e femora may be banded a p i c a l l y w i t h b l a c k ; wings h y a l i n e ; v e n a t i o n p a l e ; h i n d wing narrow; c o s t a l p r o j e c t i o n w a n t i n g ; o n l y two l o n g i t u d i n a l v e i n s p r e s e n t , e q u a l i n l e n g t h ; abdominal t e r g i t e s 2-6 p a l e s e m i - h y a l i n e , t i n g e d w i t h smoky brown; t e r g i t e s 7-10 opaque l i g h t s e p i a - b r o w n ; s t e r n i t e s w h i t i s h ; a s h o r t p r o j e c t i n g p l a t e between the bases of the f o r c e p s ; g e n i t a l i a of m o d i f i e d m o f f a t i type ( f i g . 3 ) . Nymph: Unknown D i s t r i b u t i o n : B r i t i s h Columbia No specimens of t h i s s p e c i e s were examined. -116-BAETIS INTERMEDIUS DODDS B a e t i s i n t e r m e d i u s Dodds, Needham, 1935, The B i o l o g y o f M a y f l i e s , 693 ( B i b l i o g r a p h y ) A d u l t : Thorax dark brown; h i n d wing t w i c e as l o n g as wide, t h e margins rounded, not p a r a l l e l t o one a n o t h e r ; c o s t a l p r o j e c t i o n w e l l d e v e l o p e d , a c u t e , not c u r v e d ; 3 l o n g i t u d i n a l v e i n s i n h i n d w i n g , f i r s t 2 a p p r o x i -m a t e l y e q u a l i n l e n g t h , . 2 n d not f o r k e d ; 3 r d v e i n f a i n t , r u n n i n g c l o s e t o h i n d m a r g i n , and e n d i n g basad o f m i d d l e on h i n d m a r g i n ; u s u a l l y no c r o s s v e i n s ; one s h o r t i n t e r c a l a r y between v e i n s 2 and 3; abdominal segments 2-6 o l i v a c e o u s to deep brown; g e n i t a l i a of m o f f a t i t y p e ; no t u b e r c l e a t i n n e r a p i c a l margin o f b a s a l f o r c e p s j o i n t ; no exc a v -a t i o n on s p i n e botween the bases o f t h e f o r c e p s . Nymph: G i l l s o f segments 6 and 7 o v a l and rounded; m i d d l e t a i l about l / 6 the l e n g t h o f the o u t e r ones; t a i l s unbanded. D i s t r i b u t i o n : C o l o r a d o , B r i t i s h Columbia No specimens o f t h i s s p e c i e s were examined. BAETIS 3ESMQNDENSIS McDUNNOUGH B a e t i s j e s m o n d e n s i s McDunnough, McDunnough, 1938, Can. E n t . , 70:25 ( B i b l i o g r a p h y ) A d u l t : Eyes o f male r a t h e r s m a l l ; femora l i g h t smoky brown; wings h y a l i n e ; v e n a t i o n f a i n t l y b r o w n - t i n t e d , e s p e c i a l l y t he C and Sc; i n t e r c a l a r i e s o f C and Sc m o d e r a t e l y l o n g but p r a c t i c a l l y l a c k i n g i n 1 s t c o s t a l i n t e r s p a c e ; c r o s s v e i n s h e a v i e r and deeper brown i n fe m a l e ; h i n d wing w i t h 3 l o n g i t u d i n a l v e i n s ; v e i n s 1 and 2 bend a v e r y l i t t l e towards -117-each o t h e r a t o u t e r m a r g i n ; v e i n 3 extends 2/3 the l e n g t h of the h i n d m a r g i n ; c o s t a l p r o j e c t i o n p r o m i n e n t , a c u t e , not c u r v e d ; w e l l d e f i n e d i n t e r c a l a r y between v e i n s 2 and 3; abdominal t e r g i t e s 1-6 s e m i - h y a l i n e , u n i f o r m l y smoky brown, r u d d i e r i n the f e m a l e ; the p o s t e r i o r edges of t h e t e r g i t e s are n a r r o w l y and o b s c u r e l y p a l e ; a n t e r i o r to t h i s i s a f a i n t dark t r a n s v e r s e l i n e i n each t e r g i t e ; a b d ominal t e r g i t e s 7-10 opaque, deep r u s s e t brown. Nymph: Unknown D i s t r i b u t i o n : B r i t i s h C o l umbia No specimens of t h i s s p e c i e s were examined. BAETIS PARVUS DODDS B a e t i s p a r v u s Dodds, Needham, 1935, The B i o l o g y of I T I a y f l i e s , 696 ( B i b l i o g r a p h y ) A d u l t : T u r b i n a t e eyes moderate i n s i z e , dark orange brown i n d r i e d specimens; t h o r a x deep b l a c k i s h brown w i t h the t i p of the s c u t e l l u m p a l e r ; l e g s w h i t i s h ; wings h y a l i n e ; v e n a t i o n p a l e ; f o r e w i n g w i t h 5 t o B s t i g m a t i c c r o s s v e i n s , o f t e n w i t h s h o r t h o r i z o n t a l v e i n s between them, a s l a n t , o f t e n i n c o m p l e t e on the s u b c o s t a l m a r g i n , and sometimes f o r k i n g toward the s u b c o s t a ; u s u a l l y one s h o r t i n t e r c a l a r y i n the f i r s t i n t e r s p a c e , t h o s e of the 2nd i n t e r s p a c e s l i g h t l y s h o r t e r t h a n the f o l l o w i n g p a i r s ; h i n d wing u n u s u a l l y wide f o r i t s l e n g t h ; c o s t a l p r o j e c t i o n w e l l d e v e l o p e d , a c u t e ; 3 l o n g i t u d i n a l v e i n s , the 1 s t and 2nd a p p r o x i m a t e l y e q u a l i n l e n g t h ; the 2nd v e i n f o r k e d about l / 3 the d i s t a n c e from the base; 1, 3 o r 4 i n t e r c a l a r i e s i n t h i s f o r k , one b e i n g l o n g and the o t h e r s s h o r t ; 3 r d v e i n may be weakly d e v e l o p e d , end near m i d d l e of h i n d m a r g i n ; f i r s t abdominal t e r g i t e dark brown,; -118-t e r g i t e s 2-6 h y a l i n e w h i t e ; t e r g i t e s 7-10 opaque, brown, w h o l l y o r p a r t l y s u f f u s e d w i t h deep r o s e ; s t e r n i t e 1 l i g h t brown, r e s t opaque creamy w h i t e , shaded and marked w i t h r o s e ; no dark s p i r a c u l a r m a r k i n g s ; t u b e r c l e on i n n e r a p i c a l margin o f b a s a l f o r c e p s j o i n t a b s e n t or p o o r l y d e v e l o p e d ; g e n i t a l i a of i n t e r c a l a r i e s t y p e . ( f i g . 3) Mymph: G i l l s o f segments 6 and 7 o v a l , rounded; m i d d l e t a i l 3/4 t o 5/6 the l e n g t h of the o u t e r ones; t a i l s unbanded. D i s t r i b u t i o n : IKlontana, Wyoming, A l b e r t a , West V i r g i n i a , B r i t i s h C o l u m bia. M a t e r i a l Examined: No specimens of t h i s s p e c i e s were examined. One v e r y young, w h i t e u n p a t t e r n e d specimen t a k e n by Mr. R. Humphries a t C o r b e t t Lake, B r i t i s h C olumbia (IX.21.63) seems to be of t h i s s p e c i e s . BAETIS PERSECUTA McDUNNOUGH B a e t i s p e r s e c u t a McDunnough, McDunnough, 1939, Can. E n t . , 71:52 ( B i b l i o g r a p h y ) A d u l t : S m a l l o v a l t u r b i n a t e eyes; f o r e femora o f male w h i t i s h , s u f f u s e d w i t h smoky; femora of f e m a l e l i g h t smoky amber; wings h y a l i n e ; v e n a t i o n p a l e i n male, t i n g e d w i t h brown i n f e m a l e ; i n t e r c a l a r i e s o f f i r s t i n t e r s p a c e v e r y weak; c o s t a l p r o j e c t i o n o f h i n d wing w e l l d e v e l o p e d ; t h i r d l o n g i t u d i n a l v e i n weak i n male, o b s o l e s c e n t i n f e m a l e ; no d e f i n i t e i n t e r c a l a r i e s i n h i n d wing; abdominal t e r g i t e s 1-6 o f male h y a l i n e w h i t i s h w i t h a f a i n t smoky t i n g e ; t e r g i t e s 7-10 l i g h t wood-brown; abdominal t e r g i t e s of female brown; g e n i t a l i a o f m o f f a t i t y p e ; i n n e r a p i c a l margin of f i r s t j o i n t of f o r c e p s more b u l g i n g than u s u a l , \u00E2\u0080\u00A2119-but not t u b e r c u l a t e . Nymph: Unknown D i s t r i b u t i o n ; B r i t i s h Columbia No specimens o f t h i s s p e c i e s were examined. B a e t i s sp. 1 A d u l t ; Unknown Nymph; L a r g e , s i n g l e g i l l s on segments 1-7; abdominal t e r g i t e s brown, t e r g i t e s 4 and 5 p a l e ; 2 dark s p o t s on each t e r g i t e ; m i d d l e t a i l r e p r e s e n t e d by an unsegmented r u d i m e n t . E c o l o g y ; Specimens of t h i s s p e c i e s were t a k e n from the m i d d l e and edges of the A l o u e t t e R i v e r , from a depth of 1 t o 2 f e e t g e n e r a l l y , a l t h o u g h t h e y have a l s o been c o l l e c t e d a t depths of 2 i n c h e s and 5 f e e t . The s u b s t r a t e s v a r i e d from mud, t h r o u g h sand, g r a v e l , r o c k s , b o u l d e r s , t o b e d r o c k . The most common of t h e s e were c o a r s e g r a v e l and s m a l l r o c k s . The c u r r e n t was u s u a l l y a g e n t l e r i p p l e , a l t h o u g h they have been t a k e n i n r a p i d s and i n q u i e t e r w a t e r . They were c o l l e c t e d the year round. D i s t r i b u t i o n ; B r i t i s h Columbia M a t e r i a l Examined: 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) V.19.59 (N.3. F i l m e r ) ; 2 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) VI.2.59 (N.3. F i l m e r ) ; 1 Nymph, B r i t i s h C o l u m b i a : Loon Creek ( C l i n t o n ) (H. L o r z ) , 2 Nymphs, B r i t i s h C o l u m b i a : Nr. H e l l ' s Gate, VI.19.59 (G.G.E. S c u d d e r ) ; 1 Nymph, B r i t i s h C o l u m b i a : C u l t u s Lake, V.9.59 (G.G.E. S c u d d e r ) , 6 Nymphs, B r i t i s h C o l u m b i a : N i c o l a C r . -120-B a e t i s sp. 2 A d u l t : Unknouin Nymph: L a r g e , s i n g l e g i l l s on segments 1 to 7; abdominal t e r g i t e s 5, 8 and 10 p a l e r than the o t h e r s ; two dark s u b m e d i a l d o t s on t e r g i t e s 5 and 8 or 4 and 5; t a i l s t h r e e , m i d d l e t a i l u s u a l l y l / 6 the l e n g t h of t he l a t e r a l s , but may e x t e n d to 1/2 t h e i r l e n g t h . E c o l o g y : Specimens of t h i s s p e c i e s have been t a k e n from the m i d d l e and edges of v a r i o u s l o c a t i o n s on the A l o u e t t e R i v e r , i n depths of 1 to 5 f e e t , a l t h o u g h g e n e r a l l y they were not found a t a depth g r e a t e r than 2 t o 3 f e e t . The stream bed v a r i e d from mud, t h r o u g h sand, g r a v e l , r o c k s and b o u l d e r s , t o bedr o c k . The c u r r e n t v a r i e d from q u i e t p o o l s t o r a p i d s and f a l l s . T h i s s p e c i e s was t a k e n from Dune 1959 t o the f o l l o w i n g F e b r u a r y . D i s t r i b u t i o n : B r i t i s h Columbia M a t e r i a l Examined: 3 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) VI.23.59 (N.3. F i l m e r ) ; 9 Nymphs, B r i t i s h C o l u m b i a : N i c o l a C r . B a e t i s s p . 3 A d u l t : Unknown Nymph: A v e r a g e - s i z e d , s i n g l e g i l l s on segments 1-7; g i l l t r a c h e a t i o n i n d i s t i n c t ; abdominal t e r g i t e s u n i c o l o u r e d , w i t h no dark m a r k i n g s ; t e r g i t e 5 and 10, or o n l y 10 may be p a l e r ; t a i l s 3, m i d d l e t a i l v a r i e s from l / 2 the l e n g t h of the l a t e r a l s to a l m o s t s u b e q u a l i n l e n g t h t o them. -121-E c o l o q y : Nymphs of t h i s s p e c i e s have been t a k e n from the m i d d l e a i d edges o f v a r i o u s l o c a t i o n s on the A l o u e t t e R i v e r , from depths o f 1 to 3 f e e t , a l t h o u g h o o a s i o n a l l y from deeper, w a t e r . The s u b s t r a t e v a r i e d from mud, th r o u g h sand, g r a v e l , r o c k s , and b o u l d e r s , t o bedrock. The c u r r e n t v a r i e d from q u i e t water t o r a p i d s . They were t a k e n the y e a r round. D i s t r i b u t i o n : B r i t i s h C olumbia M a t e r i a l Examined: 3 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B. c.) V.26.59 ( N . J . F i l m e r ) ; 2 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) VI.9.59 ( N . J . F i l m e r ) ; 2 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) VI.26.59 ( N . J . . F i l m e r ) ; 2 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney, B.C.) VI.16.59 ( N . J . F i l m e r ) . B a e t i s s p . 4 A d u l t : Unknown Nymph: . Front- o f head o c h r e o u s ; wing pads dark brown; a l l abdominal t e r g i t e s brown, none p a l e r than the o t h e r s ; t e r g i t e s B, 9 and 10 w i t h s u b l a t e r a l ' d a r k l i n e s ; t a i l s 3, m i d d l e t a i l 5/6 the l e n g t h o f the l a t e r a l t a i l s . D i s t r i b u t i o n : . B r i t i s h Columbia M a t e r i a l Examined: 1 Nymph, B r i t i s h C o l u m b i a : Squamish, V I I I . 2 5 . 6 1 (G.G.E. S c u d d e r ) ; 1 Nymph, B r i t i s h C o l u mbia: Brunson Lk., VI.25.61 (G.G.E. S c u d d e r ) ; \u00E2\u0080\u00A23 Nymphs, B r i t i s h C o l u m b i a : S p r i n g h o u s e Lk., V I I . 4 . 6 3 (G.G.E. S c u d d e r ) ; 1 Nymph, B r i t i s h C o l u m b i a : P a v i l i o n , VI.30.61 (G.G.E. S c u d d e r ) ; -122-,3 Nymphs, B r i t i s h C o l u m b i a : W i l l i a m s L ake, VI.24.61 (G.G.E. S c u d d e r ) ; 41 Nymphs, B r i t i s h C o l u m b i a : Q u e s n e l , VI.24.61 (G.G.E. S c u d d e r ) . B a e t i s s p . 5 A d u l t : Unknown Nymph: F r o n t o f head l i g h t brown; wing pads l i g h t brown; abdominal t e r g i t e s brown, p a t t e r n e d w i t h d a r k e r brown; t e r g i t e s 5,6, 9 and 10 may be p a l e r ; each t e r g i t e w i t h a p a i r o f p a l e s u b l a t e r a l l i n e s ; p a t t e r n on each of t e r g i t e s 7 and 8 i s a dark median t r i a n g l e , apex d i r e c t e d a n t e r i o r l y , and a dark s p o t on each s i d e of the apex; t e r g i t e s 9 and 10 each w i t h a dark m e d i a l l i n e ; t a i l s 3, m i d d l e t a i l 5/6 the l e n g t h o f t h e l a t e r a l t a i l s . D i s t r i b u t i o n : B r i t i s h C o l umbia M a t e r i a l Examined: 1 Nymph, B r i t i s h C o l u m b i a : Uiarmspring Lk., VII.15.62 (G.G.E. . S c u d d e r ) ; the a u t h o r has a l s o examined many o t h e r nymphs of t h i s s p e c i e s t a k e n by Dr. G.G.E. Scudder, from IV.4.59 t o IX.23.63 a t the f o l l o w i n g l o c a t i o n s : B r i t i s h C olumbia - Rock Lk., S p r i n g -house Lk., B o i t a n o Lk., R i s k e C r . , R a c e t r a c k Lk., n r . P h a l e r o p e , Q u e s n e l , Ulestwick Lk., F e l k e r Lk., M c l n t y r e Lk., Brunson Lk., White Lk., N i c o l C r . , Dougout Lk., P a v i l i o n , Sorenson Lk., W i l l i a m s Lk., P h a l e r o p e Lk., Beaver Lk. B a e t i s s p . 6 A d u l t : Unknown Nymph: Wing pads may be l i g h t or dark brown; g i l l s l a r g e ; t r a c h e a t i o n d i s t i n c t ; abdominal t e r g i t e s brown, 8-10 p a l e r ; each t e r g i t e w i t h a p a i r o f p a l e s u b l a t e r a l s t r i p e s ; t e r g i t e s 8 t o 10 each w i t h a m e d i a l -123- ' and 2 l a t e r a l dark bands; t a i l s 3, m i d d l e t a i l 5/6 the l e n g t h o f t h e l a t e r a l s ' . D i s t r i b u t i o n ; B r i t i s h C olumbia M a t e r i a l Examined: 1 Nymph, B r i t i s h C o l u m b i a : N i c o l a L ake, 59 Nymphs, B r i t i s h C o l u m b i a : S p r i n g h o u s e Lk., V.5.63 (G.G.E. S c u d d e r ) . B a e t i s s p . 7 A d u l t : Unknown Nymph: G i l l s l a r g e ; t r a c h e a t i o n d i s t i n c t ; abdominal t e r g i t e s u n i c o l o u r e d ; t a i l s 3, m i d d l e t a i l l / 2 the l e n g t h of the l a t e r a l s . D i s t r i b u t i o n : B r i t i s h C olumbia M a t e r i a l Examined: 1 Nymph, B r i t i s h C o l u m b i a : R a c e t r a c k Lake, VI.21.61 (G.G.E. S c u d d e r ) . GENUS CALLIBAETIS EATON C a l l i b a e t i s , Needham, 1935, The B i o l o g y of M a y f l i e s , 657 ( B i b l i o g r a p h y ) A d u l t : S m a l l t o medium s i z e d m a y f l i e s ; b o d i e s and u s u a l l y l e g s t h i c k l y s p r i n k l e d w i t h s m a l l r e d d i s h or dark brown s p o t s , o f t e n a p p e a r i n g t o be s e t i n s m a l l d e p r e s s i o n s ; males u s u a l l y d a r k e r i n c o l o u r than the f e m a l e s ; t u r b i n a t e eyes of male m o d e r a t e l y l a r g e , l e n g t h i l y o v a l ; eyes o f female l a r g e , not s e t h i g h on the s i d e of the head; p o s t e r i o r margin of head of female s l i g h t l y e m a r g i n a t e m e d i a l l y , on each s i d e of which i s a p o s t e r i o r l y d i r e c t e d s l i g h t l y rounded l o b e ; f o r e l e g o f male s l i g h t l y s h o r t e r than the body; femur about 3/4 the l e n g t h of the t i b i a , which i s s l i g h t l y s h o r t e r or s u b e q u a l t o t a r s u s ; 1 s t j o i n t o f t a r s u s e q u a l t o j o i n t s 3 and 4; i n f o r e l e g of f e m a l e , femur -124-s u b e q u a l to t i b i a , which i s s l i g h t l y s h o r t e r than the t a r s u s ; h i n d t i b i a o f both sexes l / 2 t o 3/4 the l e n g t h of the femur, t a r s u s s l i g h t l y s h o r t e r than the t i b i a ; f o r e w i n g of f e m a l e u s u a l l y ornamented w i t h b r o w n i s h a l o n g the c o s t a l m a r g i n , and sometimes i n the d i s c ; f o r e -wing o f male may be w h o l l y h y a l i n e , o r w i t h some dark c o l o u r , but l e s s t h a n i n the f e m a l e ; f o r e w i n g u s u a l l y w i t h numerous c o s t a l c r o s s -v e i n s b e f o r e the b u l l a ; o t h e r c r o s s v e i n s u s u a l l y numerous, a l t h o u g h they may be few i n number i n some s p e c i e s ; m a r g i n a l i n t e r c a l a r i e s o c c u r r i n g s i n g l y or i n p a i r s , the number not c o n s t a n t w i t h i n any one s p e c i e s ; u s u a l l y , the i n t e r c a l a r i e s a t the t i p and i n the a n a l r e g i o n are p a i r e d , w h i l e the r e s t may be s i n g l e ; h i n d wing r e l a t i v e l y l a r g e , widened a t base; c o s t a l p r o j e c t i o n l a r g e and v e r y o b t u s e ; t h r e e l o n g i t u d i n a l v e i n s ; s e v e r a l w e l l - d e v e l o p e d ' c r o s s v e i n s , e s p e c i a l l y i n the c o s t a l r e g i o n ; a few i n t e r c a l a r i e s p r e s e n t between v e i n s 2 and 3; f o r c e p s 4 - j o i n t e d ; a s m a l l rounded or c o n i c a l \" p e n i s c o v e r \" i s p r e s e n t between the f o r c e p s b a s e s ; p o s t e r i o r margin of s t e r n i t e 9 o f f e m a l e a l m o s t s t r a i g h t . Nymph; M a x i l l a r y p a l p t w o - j o i n t e d ; c a n i n e s of m a n d i b l e s l o n g and s l e n d e r ; l a b i a l p a l p ' 3 - j o i n t e d , the d i s t a l j o i n t s h o r t and c o n i c a l ; c l a w s l o n g and s l e n d e r , 1/-2 t o 3/4 the l e n g t h of t h e t a r s u s , and d e n t i c u l a t e ; 2 p a i r s of wing buds p r e s e n t ; g i l l s l a r g e , i r r e g u l a r l y s u b o v a t e , p o i n t e d a t t i p ; g i l l s d ouble on segments 1-6 or 1-7, o r the v e n t r a l p o r t i o n b e i n g a s m a l l r e c u r v e d f l a p ; the v e n t r a l f l a p on segments 1 and 2 w e l l d e v e l o p e d , may bear a s m a l l s e c o n d a r y f l a p ; t r a c h e a t i o n p i n n a t e o r p a l m a t e , or s i m p l e on the o u t e r m a r g i n ; t a i l s t h r e e , a l l e q u a l i n l e n g t h and t h i c k n e s s . Genotype: C a l l i b a e t i s p i c t u s ( i n B a e t i s ) Eaton -125-CALLIBAETIS Key To A d u l t s 1. M a r g i n a l i n t e r c a l a r i e s s i n g l e i n f e m a l e , b a r e l y v i s i b l e . c a r o l u s T r a v e r M a r g i n a l i n t e r c a l a r i e s p a i r e d o.2. 2. U i t t a not p a t t e r n e d i n brown or b l a c k . 3. V i t t a p a t t e r n e d i n brown or b l a c k . . . 5. 3. L o n g i t u d i n a l v e i n s a l t e r n a t e l y l i g h t and dark sp. 1 L o n g i t u d i n a l v e i n s c o m p l e t e l y p a l e 4. 4. C o l o u r i n g dark. F i n e c r o s s v e i n s between Rs and Of of f o r e w i n g . . . . s p . 2 C o l o u r i n g l i g h t e r . More th a n f i v e c r o s s v e i n s between Rs and Of o f f o r e w i n g sp. 5 5. L o n g i t u d i n a l v e i n s c o m p l e t e l y p a l e sp. 3 L o n g i t u d i n a l v e i n s a l t e r n a t e l y l i g h t and d a r k . . 6 6. L a t e r a l a r e a s of mesonotum y e l l o w sp. 4 L a t e r a l a r e a s of mesonotum not p a l e r than r e s t of mesonotum.....7. 7. Abdominal t e r g i t e s u n i c o l o u r e d 8. Abdominal t e r g i t e s w i t h dark or p a l e l o n g i t u d i n a l s t r i p e s . . 10. 8. Abdomen dark brown, alm o s t b l a c k i s h . . . . c o l o r a d e n s i s Banks Abdomen r e d d i s h brown 9. 9. Wings o f male a l m o s t c l e a r w i t h two narrow widened brown p o r t i o n s on the c o s t a , s t i g m a s l i g h t l y b r o w n - t i n g e d . V i t t a of female wide, dark brown, i t s h i n d margin w i t h about 5 l o b e s . . . . . . . . . h a q e n i ( E a t o n ) U i t t a wide, i t s h i n d margin w i t h 4 l o b e s . Many h y a l i n e s p o t s i n c o s t a l c e l l .sp.7 -126-10. T e r g i t e s w i t h a dark \"median s t r i p e ( p a l e i n the m i d d l e i n the l a s t few segments) n i q r i t u s Banks T e r g i t e s w i t h a l i g h t median and 2 l i g h t submedian s t r i p e s . . s p . 6 Key To Nymphs 1. Femur w i t h a broad p r e - a p i c a l band \u00E2\u0080\u00A2 .haqeni ( E a t o n ) No such band on femur sp.8 Unknown; C a l l i b a e t i s c o l o r a d e n s i s Banks C a l l i b a e t i s n i q r i t u s Banks C a l l i b a e t i s c a r o l u s T r a v e r CALLIBAETIS CAROLUS TRAVER C a l l i b a e t i s c a r o l u s T r a v e r , Edmunds and A l l e n , 1957, Ann. E n t . Soc. Amer. 50 (4) : 320 ( B i b l i o g r a p h y ) A d u l t : A brown m a y f l y ; t u r b i n a t e eyes of male orange-brown; t h o r a c i c notum of male red-brown; t h o r a c i c notum of female y e l l o w i s h ; p o s t e r o -l a t e r a l margins of mesonotum dark red-brown; i n the male, the f o r e l e g i s b r o w n i s h ; the femora may be y e l l o w i s h b a s a l l y , t a r s i p a l e , or the e n t i r e l e g may be smoky to p a l e red-brown, the femur w i t h a d i s t i n c t p r e - a p i c a l dark band; m i d d l e and h i n d l e g s w h i t i s h o r y e l l o w i s h w h i t e , f a i n t dark band near apex of femur and o c c a s i o n a l l o n g i t u d i n a l dark s t r e a k s ; s t i p p l i n g , i f p r e s e n t , very f a i n t ; t a r s i shaded w i t h l i g h t brown; i n f e m a l e , l e g s w h i t i s h or y e l l o w i s h ; t a r s i u s u a l l y brown; femora u s u a l l y w i t h some r e d d i s h brown s t i p p l i n g ; wings h y a l i n e , i r r i d e s c e n t ; more than 35 c r o s s v e i n s ; i n male m a r g i n a l i n t e r c a l a r i e s u s u a l l y p a i r e d ; l o n g i t u d i n a l v e i n s a l t e r n a t e l y brown and p a l e ; c r o s s v e i n s p a l e ; o u t e r margins brown; u s u a l l y f a i n t b l a c k i s h -brown m a r k i n g s a l o n g the c o s t a ; extreme a p i c a l p o r t i o n o f c o s t a l -127-space shaded w i t h brown; m a r g i n a l i n t e r c a l a r i e s of female o f t e n s i n g l e , may be b a r e l y v i s i b l e ; v i t t a b l a c k i s h brown e x c e p t basad o f - c o s t a l b r a c e ; v i t t a narrow, s i n u a t e i n i t s p o s t e r i o r m a r g i n , e x t e n d i n g i n t o 4 d i s t i n c t l o b e s , the most a p i c a l of which has 3 or more s m a l l secondary l o b e s ; c o s t a l space i n t e r r u p t e d brown-and w h i t e ; c r o s s v e i n s i n v i t t a f e n e s t r a t e w i t h h y a l i n e ; c o s t a l b r a c e brown on each end and pale\" i n - t h e m i d d l e , and on each s i d e near Sc i s a brown c l o u d ; s m a l l dark c l o u d s a l o n g l o n g i t u d i n a l v e i n s , and some on the p o s t e r i o r m a r g i n ; l o n g i t u d i n a l v e i n s as i n male; abdominal t e r g i t e s of male dark red-brown, p o s t e r i o r m argins deeper; each t e r g i t e w i t h two dark submedian l i n e s , u s u a l l y s e p a r a t e d by a narrow p a l e median l i n e , and f l a n k e d by 2 p a l e r y e l l o w -i s h s t r e a k s ; dark l i n e a l o n g p l e u r a l f o l d ; s t i p p l i n g m o d e r a t e l y dense and r e g u l a r ; s t e r n i t e s p a l e r y e l l o w i s h - brown, w i t h dark submedian s t r e a k s ; s t i p p l i n g f i n e r ; a p i c a l s t e r n i t e s o f t e n opaque creamy o r y e l l o w i s h w h i t e ; abdomen of female s i m i l a r , but p a l e r ; f o r c e p s and t a i l s p a l e , j o i n i n g s n a r r o w l y b l a c k i s h . Nymph; Unknown D i s t r i b u t i o n : C a l i f o r n i a , B r i t i s h C olumbia M a t e r i a l Examined:. 1 Female, B r i t i s h C o l u m b i a : Vernon, VII.26.63 (G.G.E. Scudder) 2 Females, B r i t i s h C o l u m b i a : L y t t o n , V I I I . 3 0 . 3 1 ( G . J . S p e n c e r ) , 1 Female, B r i t i s h C o l u m b i a , Vernon, VII.10.48 (D. E v a n s ) . CALLIBAETIS C0L0RADENSIS BANKS C a l l i b a e t i s c o l o r a d e n s i s Banks, Needham, 1935, The B i o l o g y o f May-f l i e s , 664 ( B i b l i o g r a p h y ) A d u l t : ( f e m a l e ) A dark brown m a y f l y ; t h o r a x dark brown; femora f i n e l y s t i p p l e d -128-u i i t h brown; t i p s of t a r s i brown; c r o s s v e i n s of f o r e w i n g b e h i n d the v i t t a more than 35, u s u a l l y s e v e r a l c l o s e to h i n d m a r g i n , a r r a n g e d i n 2 or more i r r e g u l a r rows a c r o s s the wing; most c r o s s v e i n s w h i t e ; m a r g i n a l i n t e r c a l a r i e s u s u a l l y p a i r e d ; v i t t a dark brown, broken up i n t o t h r e e main s p o t s , one a p i c a l , one s t i g m a t i c , and one b e f o r e the m i d d l e , w i t h a s m a l l e r one a t base; b a s a l c o s t a l space h y a l i n e ; l o n g i t u d i n a l v e i n s brown i n p l a c e s , or a l t e r n a t e l y l i g h t and d a r k ; no c l o u d s on v e i n s ; h i n d wing l o n g and narrow; c o s t a l margin somewhat \u00E2\u0080\u00A2 e m a r g i n a t e b e h i n d the c o s t a l p r o j e c t i o n ; m a r g i n a l i n t e r c a l a r i e s v e r y l o n g , r e s e m b l i n g l o n g i t u d i n a l v e i n s , and 3 or 4 i n number; c r o s s -v e i n s t e n d t o be a r r a n g e d i n groups of 2; abdomen b l a c k i s h brown, r e l a t i v e l y s h o r t . Nymph: Unknown D i s t r i b u t i o n : B r i t i s h C o l u m b i a , C o l o r a d o No specimens of t h i s s p e c i e s were examined. CALLIBAETIS HAGENI (EATGN) C a l l i b a e t i s h a q e n i ( E a t o n ) , Needham, 1935, The B i o l o g y o f M a y f l i e s , 668 ( B i b l i o g r a p h y ) A d u l t : (Female) A p i c e o u s s p e c i e s ; d o r s a l s u t u r e s of notum y e l l o w i s h ; d a r k e r , p o l i s h e d i n male; l e g s brown i n both s e x e s , femora d e n s e l y , f i n e l y , and i n c o n s p i c u o u s l y s p e c k l e d ; more th a n 35 c r o s s v e i n s b e h i n d the v i t t a o f the f o r e w i n g , u s u a l l y s e v e r a l c l o s e to the h i n d m a r g i n , and a r r a n g e d i n 2 or more i r r e g u l a r rows a c r o s s the wing; c r o s s v e i n s m o s t l y w h i t e ; m a r g i n a l i n t e r c a l a r i e s m o s t l y p a i r e d , a few s i n g l e ; v i t t a o f female dark brown, wide, e x t e n d i n g i n i t s p o s t e r i o r margin -129-i n t o 5 l o b e s ; the second b e i n g the l a r g e s t ; b a s a l c o s t a l space i n -c l u d e d i n v i t t a ; b e h i n d the v i t t a , a l o n g the l o n g i t u d i n a l v e i n s , are 3 rows of brown s p o t s , the m i d d l e one b e i n g the l a r g e s t , l o n g i t u d i n a l v e i n s i n t e r r u p t e d brown and w h i t e , as i s the o u t e r margin of the wing; i n t e r c a l a r i e s brown, sometimes i n a f a i n t b r o w n i s h c l o u d ; e r o s s v e i n s i n the v i t t a f e n e s t r a t e w i t h h y a l i n e ; s t i g m a t i c c r o s s v e i n s few \" i n number, a s l a n t , f e n e s t r a t e , l e s s so and f a i n t i n male; c l o u d s on c r o s s v e i n s ; wing of male a l m o s t c l e a r , w i t h 2 brown widened p o r t i o n s on the c a s t a ; s t i g m a s l i g h t l y b r o w n - t i n g e d ; abdomen deep r e d d i s h brown; a l m o s t b l a c k i s h d o r s a l l y , p a l e r v e n t r a l l y ; t h i c k l y s t i p p l e d ; t a i l s w h i t e , j o i n i n g s b l a c k . Nymph: Femur w i t h a broad p r e - a p i c a l band; t a i l s w h o l l y p a l e , or w i t h a narrow dark band near t i p o n l y . D i s t r i b u t i o n : Oregon, C o l o r a d o , C a l i f o r n i a , Wyoming, Montana, Washington, New York, B r i t i s h C o l u m b i a . No specimens of t h i s s p e c i e s were examined. CALLIBAETIS NIGRITUS BANKS C a l l i b a e t i s n i q r i t u s Banks, Needham, 1935, The B i o l o g y of M a y f l i e s , 669 ( B i b l i o g r a p h y ) A d u l t : (Male) A dark brown m a y f l y ; t h o r a c i c notum b l a c k i s h ; f o r e l e g s b l a c k i s h ; m i d d l e and h i n d l e g s p a l e , femora d a r k e r b e f o r e apex, t a r s i d a r k e r ; femora f i n e l y and r e g u l a r l y s t i p p l e d ; c r o s s v e i n s of f o r e w i n g b e h i n d \u00E2\u0080\u00A2 v i t t a more than 35, u s u a l l y s e v e r a l c l o s e to h i n d m a r g i n , a r r a n g e d i n 2 or more r e g u l a r rows a c r o s s the wing; i n t e r c a l a r i e s m o s t l y i n p a i r s ; -130-wings h y a l i n e ; l o n g i t u d i n a l v e i n s a l t e r n a t e l y w h i t e and b l a c k ; c r o s s -v e i n s m o s t l y p a l e ; o u t e r margin a l t e r n a t e l y dark and p a l e ; c o s t a l a r e a marked w i t h b l a c k s p o t s , w i t h v a r i o u s d o t s on c o s t a l m a r g i n , and s t r e a k s and do t s a l o n g v e i n s and beyond the m i d d l e , two b e i n g l a r g e r t h a n the o t h e r s ; abdominal t e r g i t e s w i t h a d a r k e r median s t r i p e which i s p a l e i n the m i d d l e on the a p i c a l segments; s t e r n i t e s w i t h a p a i r of dark submedian s t r i p e s ; f o r c e p s and t a i l y e l l o w i s h . Nymph: Unknown D i s t r i b u t i o n : C o l o r a d o , B r i t i s h Columbia M a t e r i a l Examined: 3 Male, B r i t i s h C o l u m b i a : C h i l c o t i n , V.28.63 (G.G.E. S c u d d e r ) ; 1 Male, B r i t i s h C o l u m b i a : S p r i n g h o u s e Lake ( C a r i b o o ) V.25.63 (G.G.E. S c u d d e r ) ; 1 Male, B r i t i s h C o l u m b i a : C h i l c o t i n , VI.17.63 (G.G.E. S c u d d e r ) . C a l l i b a e t i s s p . 1 A d u l t : (Male) L a t e r a l a r e a s of mesonotum y e l l o w ; l e g s y e l l o w i s h - r e d ; more than 35 c r o s s v e i n s i n f o r e w i n g ; m a r g i n a l i n t e r c a l a r i e s p a i r e d ; no dark v i t t a ; l o n g i t u d i n a l v e i n s a l t e r n a t e l y l i g h t and d s r k , s t r o n g l y so i n c o s t a l v e i n s ; no c l o u d s on wings; abdominal t e r g i t e s dark r e d d i s h -brown; v e n t e r p a l e and l i g h t l y s t i p p l i e d ; t a i l s and g e n i t a l i a p a l e . Nymph: Unknown. D i s t r i b u t i o n : B r i t i s h Cciimbia M a t e r i a l Examined: 1 Male, B r i t i s h C o l u m b i a : L y t t o n , V I I I . 9 . 3 1 (G.3. S p e n c e r ) . -131-C a l l i b a e t i s sp.. 2 A d u l t : (fflale) T h i s s p e c i e s e x a c t l y r e s s e m b l e s C a l l i b a e t i s sp. 1, w i t h the d i f f e r e n c e t h a t t h e r e i s a b s o l u t e l y no p i g m e n t a t i o n i n the wing membrance or v e n a t i o n ; t h e r e are 5 c r o s s v e i n s between the Of and Rs of the f o r e w i n g . Nymph: Unknown D i s t r i b u t i o n : B r i t i s h C o l u m b i a M a t e r i a l Examined: 1 Male, B r i t i s h C o l u m b i a : L y t t o n , V I I I . 9 . 3 1 (G.3. S p e n c e r ) , 1 M a l e , B r i t i s h C o l u m b i a : Q u e s n e l , V I I I . 1 2 . 4 8 (H.R. M c C a r t h y ) , 1 Male, B r i t i s h C o l u m b i a : N i c o l a , V I I I . 3 0 . 2 5 ( G . J . S p e n c e r ) 1 M a l e , B r i t i s h C o l u m b i a : Nanaimo, V I I . 1 9 . 6 1 (G.G.E. S c u d d e r ) . C a l l i b a e t i s s p . 3 A d u l t : (fflale) Very s i m i l a r t o C a l l i b a e t i s s p . 1, mesonotum r e d d i s h brown; c r o s s v e i n s o f f o r e w i n g more numerous than i n C a l l i b a e t i s s p . 1; l o n g i t u d i n a l v e i n s not a l t e r n a t e l y l i g h t and d a r k ; v i t t a c o n s i s t i n g of a l t e r n a t e l y l i g h t and dark a r e a s ; s t i g m a t i c a r e a y e l l o w i s h . Nymph: Unknown D i s t r i b u t i o n : B r i t i s h Columbia M a t e r i a l Examined: '. . 1 fflale, B r i t i s h C o l u m b i a : P a v i l i o n fflt., VI.27.43 (G.3. S p e n c e r ) , 1 fflale, B r i t i s h C o l u m b i a : Q u e s n e l , VI.3.48 (G.3. S p e n c e r ) . -132-C a l l i b a e t i s sp. 4_ A d u l t ( m a l e ) : L a t e r a l a r e a s o f mesonotum y e l l o w ; l e g s y e l l o w ; more than 35 c r o s s v e i n s i n f o r e w i n g ; m a r g i n a l i n t e r c a l a r i e s p a i r e d ; l o n g i t u d i n a l v e i n s a l t e r n a t e l y l i g h t and dark; v i t t a wide, e x t e n d i n g on p o s t e r i o r m a r g i n i n t o 4 l o b e s ; many h y a l i n e s p o t s i n c o s t a l c e l l ; no c l o u d s on w i n g s ; abodminal markings much as i n C a l l i b a e t i s n i q r i t u s ; t a i l s p a l e , j o i n i n g s d a r k . Nymph: Unknown D i s t r i b u t i o n : B r i t i s h Columbia m a t e r i a l Examined: 1 M a l e , B r i t i s h C o l u m b i a : P a v i l i o n fflt., VI.27.43 ( G . J . Sp e n c e r ) C a l l i b a e t i s sp. 5 A d u l t : ( m a l e ) T h i s s p e c i e s i s s i m i l a r t o C a l l i b a e t i s s p . 2, but l i g h t e r i n c o l o u r ; more th a n 5 c r o s s v e i n s between Rs and Of of f o r e w i n g . Nymph: Unknown D i s t r i b u t i o n : B r i t i s h Columbia m a t e r i a l Examined: 6 males, B r i t i s h C o l u m b i a : Kamloops, V I I I . 4 . 3 4 , ( G . J . S p e n c e r ) , 2 males, B r i t i s h C o l u m b i a : N i c o l a , V I I I . 3 0 . 2 5 ( G . J . S p e n c e r ) , 1 male, B r i t i s h C o l u m b i a : Q u e s n e l , VII.23.48 ( G . J . S p e n c e r ) , 1 male, B r i t i s h C o l u mbia: Q u e s n e l , V I I I . 1 2 . 4 8 (H.R. lYlcCarthy), 2 males, B r i t i s h C o l u m b i a : Okanagan Lake, VII.25.35 ( J . L . McHugh), 3 fflales, B r i t i s h C o l u m b i a : N i c o l a , V I I I . 2 1 . 3 2 ( G . J . S p e n c e r ) . C a l l i b a e t i s sp. 6 A d u l t : (fflale) A s p e c i e s v e r y s i m i l a r to C a l l i b a e t i s sp. 4; l a t e r a l a r e a s o f . -133-mesonotum brown; l e g s and t a i l s b r o w n i s h y e l l o w ; abdominal markings d a r k e r than i n C a l l i b a e t i s sp. 4, w i t h each t e r g i t e h a v i n g a median and 2 submedian p a l e s t r e a k s . Nymph: Unknown D i s t r i b u t i o n : B r i t i s h C o lumbia M a t e r i a l Examined: 1 M a l e , B r i t i s h C o l u m b i a : B l a n k e t Mt., V I I I . 1 . 4 6 C a l l i b a e t i s s p . 7 A d u l t : (Female) C l o s e l y r e s e m b l i n g C a l l i b a e t i s s p . 4, but abdominal t e r g i t e s and s t e r n i t e s r e d d i s h brown; mesonotum a l l brown; l e g s brown; a l a r g e r s p e c i e s . Nymph: Unknown D i s t r i b u t i o n : B r i t i s h Columbia M a t e r i a l Examined: 1 Female, B r i t i s h C o l u m b i a : N i c o l a , UII..10.32 (G.3. S p e n c e r ) C a l l i b a e t i s sp. 8 A d u l t : Unknown Nymph:-No p r e - a p i c a l band on femur; g i l l s on segments 1-7 l a r g e , h e a v i l y t r a c h e a t e d ; no l i g h t s p o t s on t e r g i t e s ; t a i l s h e a v i l y f r i n g e d , dark a t t i p s . E c o l o g y : Specimens of t h i s s p e c i e s were t a k e n from the edges o n l y o f the A l o u e t t e R i v e r . The s u b s t r a t e was mud, s i l t , and i n one c a s e , sand and . g r a v e l . They,were t a k e n at a depth of 1-4 f e e t , i n q u i e t , slow w a t e r , a l t h o u g h i n one case (from.sand and g r a v e l ) , the c u r r e n t -134-produced r i p p l e s . A l l specimens were c o l l e c t e d on J u l y 1, 1959, and were found a t not any o t h e r t i m e . D i s t r i b u t i o n ; B r i t i s h Columbia M a t e r i a l Examined: 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney,.B.C.) VII.1,59 ( N . J . F i l m e r ) GENUS CENTROPTILUM EATON C e n t r o p t i l u m , Needham, 1935, The B i o l o g y of M a y f l i e s , 705 ( B i b l i o g r a p h y ) A d u l t ; S m a l l , p a l e m a y f l i e s ; t u r b i n a t e eyes of male moderate t o l a r g e , - u s u a l l y j b n g t h i l y o v a l ; eyes o f female l a r g e , s e t h i g h on the s i d e s o f the head; p o s t e r i o r margin of head of female d i s t i n c t l y e m a r g i nate m e d i a l l y ; f o r e l e g o f male as l o n g as body; f o r e femur l / 2 to 2/3 the l e n g t h o f the t i b i a , w hich i s s l i g h t l y s h o r t e r t h a n the t a r s u s ; i n f e m a l e , f o r e femur s l i g h t l y l o n g e r than the 1 t i b i a , w h i c h i s a l i t t l e l o n g e r than the t a r s u s ; f i r s t j o i n t o f t a r s u s e q u a l t o j o i n t s 2, 3 and 4 i n h i n d l e g of both s e x e s ; t a r s u s , t i b i a , and femur sub-e q u a l ; m a r g i n a l i n t e r c a l a r i e s o f f o r e w i n g o c c u r s i n g l y ; no c o s t a l c r o s s v e i n s b e f o r e the b u l l a ; h i n d wing s m a l l , narrow, and e l o n g a t e ; c o s t a l p r o j e c t i o n c u r v e d ; two l o n g i t u d i n a l v e i n s ; c r o s s v e i n s absent or few; b a s a l abdominal segments of male u s u a l l y p a l e y e l l o w i s h o r w h i t i s h , o f t e n w i t h e x t e n s i v e ruddy or brow n i s h m a r k i n g s ; f e m a l e s p a l e r , o f t e n l i g h t r e d d i s h - b r o w n ; b a s a l f o r c e p s j o i n t s wide a p a r t , s t o u t , u s u a l l y s l i g h t l y w i d e r than l o n g ; second j o i n t s t o u t , o f t e n - p r o l o n g e d i n w a r d on i t s o u t e r margin; t h i r d j o i n t l o n g and s l e n d e r , f r e q u e n t l y bowed; d i s t a l j o i n t sometimes h a l f as l o n g as t h i r d j o i n t , u s u a l l y s h o r t e r , c l a v a t e , 2 or 3 t i m e s as l o n g as wide; a l a r g e -135-\" p e n i s c o v e r \" between b a s a l j o i n t s ; p o s t e r i o r margin o f 9 t h s t e r n i t e o f female p r o l o n g e d backwards ve r y s l i g h t l y m e d i a l l y . Nymph; M a x i l l a r y p a l p 3 - j o i n t e d , e x t e n d i n g beyond the t i p of the g a l e a -l a c i n i a ; c a n i n e s o f m a n d i b l e s l o n g , s l e n d e r , a n d s h a r p - p o i n t e d , or s h o r t e r and s t o u t e r ; l a b i a l p a l p 3 - j o i n t e d , d i s t a l j o i n t d i l a t e d and t r u n c a t e a p i c a l l y ; c l a w s l o n g and s l e n d e r l / 2 t o 3/4 t h e l e n g t h o f the t a r s i , not d e n t i c u l a t e ; 2 p a i r s o f wing buds; g i l l s u s u a l l y s i n g l e , may be double on segments 1-6, the second p o r t i o n c o n s i s t i n g of a s m a l l r e c u r v e d d o r s a l f l a p ; t r a c h e a t i o n p i n n a t e , may be on i n n e r s i d e o n l y ; t a i l s t h r e e , a p p r o x i m a t e l y e q u a l i n l e n g t h and t h i c k n e s s . Genotype; C e n t r o p t i l u m l u t e o l u m ( i n Ephemera) M u l l e r CENTROPTILUM Key To A d u l t s 1. Abdominal t e r g i t e s 7-10 opaque creamy w h i t i s h . I n n e r margin of second f o r c e p s j o i n t w i t h a p o o r l y d e v e l o p e d t u b e r c l e . Eyes orange brown. Mesothorax y e l l o w brown........album McD Abdominal t e r g i t e s 7-10 not w h i t i s h . Inner margin o f f o r c e p s j o i n t w i t h a d i s t i n c t t u b e r c l e on i n w a r d b u l g e . 2. 2. I n n e r margin of second f o r c e p s j o i n t d i s t i n c t l y and p r o m i n e n t l y t u b e r c u l a t e . D i s t a l j o i n t o f f o r c e p s v e r y l o n g . Eyes b l a c k -brown. Mesothorax b l a c k . Abdominal t e r g i t e s 2 - 6 h y a l i n e w h i t e . conturbatum McD Inner margin o f second j o i n t of f o r c e p s may p o s s e s s a d i s t i n c t i n w a r d b u l g e , but i s not t u b e r c u l a t e . D i s t a l j o i n t of f o r c e p s i s s h o r t e r , ^yes not b l a c k - b r o w n . Mesothorax not b l a c k . Abdominal t e r g i t e s 2-6 not h y a l i n e w h i t e 3. -136-3. A d i s t i n c t t u b e r c l e i s p r e s e n t between the bases of the f o r c e p s l i m b s . T e r g i t e s 2-4 w i t h narrow ruddy p o s t e r i o r m a r g i n s , 7-9 c h o c o l a t e brown, 10 y e l l o w i s h , flflesothorax deep o l i v e brown. Eyes orange-brown b i f u r c a t u m HflcD No t u b e r c l e between the bases of the f o r c e p s l i m b s . LUedge shaped ruddy l a t e r a l m a rkings on t e r g i t es 2\u00E2\u0080\u00946, 7\u00E2\u0080\u009410 red-brown, fflesothorax o l i v a c e o u s . Eyes r e d . b e l l u m fflcD Key To Nymphs 1. G i l l s s i n g l e on a l l segments 2. G i l l s double on some or a l l segments...... 3. 2. Abdominal segments 7-10 l a r g e l y shaded w i t h brown. L a t e r a l edges of a l l t e r g i t e s p a l e , w i t h a brown t r a n s v e r s e band on each. G i l l t r a c h e a t i o n q u i t e d i s t i n c t , u s u a l l y p i n n a t e . . . . album McD Abdominal t e r g i t e s brown, p a t t e r n e d w i t h 3 p a l e s p o t s on each. T e r g i t e s 7 and 10 l a r g e l y p a l e . G i l l s t r a c h e a t i o n not d i s t i n c t sp. 1 3. G i l l s d ouble on segments 1-7. T a i l s w i t h a dark a p i c a l band '.. b e l l u m fflcD G i l l s double, on segments 1-2. No banded t a i l 4. 4. F a i n t p a t t e r n on t e r g i t e s , but p o s t e r i o r b o r d e r s dark brown, .sp. 3 T e r g i t e s u n i c o l o u r e d on l a t e r a l edges l a r g e l y p a l e . . . . . 5. 5. No p a t t e r n on t e r g i t e s sp. 4 Abdominal t e r g i t e s 7-10 l a r g e l y shaded w i t h brown. L a t e r a l edges of a l l t e r g i t e s p a l e , w i t h brown t r a n s v e r s e band on each... sp. 2 -137-Unknown: . C e n t r o p t i l u m b i f u r c a t u m IYlcD C e n t r o p t i l u m conturbatum IYlcD CENTROPTILUM ALBUM McDUNNOUGH C e n t r o p t i l u m album McDunnough, Needham, 1935, The B i o l o g y of May-f l i e s , 708 ( B i b l i o g r a p h y ) A d u l t ; . T u r b i n a t e eyes orange-brown; mesonotum p a l e ochreous w i t h brown s h a d i n g , s c u t e l l u m and p o s t e r i o r p o r t i o n a l m o s t e n t i r e l y w h i t e w i t h f a i n t p i n k s h a d i n g ; metanoturn deep brown p o s t e r i o r l y , a n t e r i o r margin w h i t e w i t h p i n k i s h s h a d i n g , and a median dark s p o t ; p l e u r a and s t e r n a deep brown; l e g s w h i t e ; wings h y a l i n e ; v e n a t i o n p a l e ; h i n d wing v e r y narrow; c o s t a l p r o j e c t i o n p r o m i n e n t ; abdominal t e r g i t e s h y a l i n e i n male, y e l l o w i s h o r w h i t i s h ; t e r g i t e s 7-10 opaque, creamy w h i t e ; t a i l s w h i t e ; i n w a r d b u l g e o f second f o r c e p s j o i n t s l i g h t . Nymph; G i l l s s i n g l e on segments 1-7 (no r e c u r v e d f l a p ) ; g i l l t r a c h e a t i o n n o r m a l l y p i n n a t e , d i s t i n c t ; abdominal t e r g i t e s 7-10 l a r g e l y shaded w i t h brown. D i s t r i b u t i o n ; B r i t i s h C o l u m b i a , Eastern N o r t h America No specimens o f t h i s s p e c i e s were examined. CENTROPTILUM BELLUM McDUNNOUGH C e n t r o p t i l u m b e l l u m McDunnough, Needham, 1935, The B i o l o g y of May-f l i e s , 709 ( B i b l i o g r a p h y ) A d u l t : T u r b i n a t e eyes deep r e d d i s h ; mesonotum o l i v a c e o u s shaded w i t h y e l l o w i s h s u b d o r s a l l y ; l a t e r a l and p o s t e r i o r margins t i n g e d w i t h -138-ruddy; metanotum deep o.live ..brown, s u t u r e s d a r k e r , a n t e r i o r d o r s a l p o r t i o n shaded w i t h ruddy; l e g s y e l l o w i s h w h i t e ; wings h y a l i n e ; h i n d wing m o d e r a t e l y b r o a d ; two l o n g i t u d i n a l v e i n s ; abdominal t e r g i t e s 2-6 s e m i - h y a l i n e , p a l e y e l l o w i s h , the p o s t e r i o r margins n a r r o w l y ruddy brown e n d i n g i n f a i n t s m a l l r e d d i s h p a t c h e s i n the s p i r a c u l a r a r e a ; t e r g i t e s 7-10 b r i g h t ruddy brown; s t e r n i t e s 2-6 p a l e ; s t e r n i t e s 7-10 opaque y e l l o w i s h shaded l a t e r a l l y w i t h r e d d i s h and w i t h f a i n t ruddy p o s t e r i o r m a r g i n s ; s p i r a c u l a r l i n e b l a c k i s h ; f o r c e p s and t a i l s w h i t e . Nymph; G i l l s double on a l l segments; abdominal t e r g i t e s marked w i t h brown; t e r g i t e s 4, 5, 7, 8, and 10 p a l e r ; , t a i l s dark i n a p i c a l l / 3 . D i s t r i b u t i o n - : B r i t i s h C o lumbia, Quebec. M a t e r i a l Examined: 1 Nymph, B r i t i s h C o l u m b i a : W i l l i a m s Lake, V I . 2 4 i 6 1 (G.G.E. Scudder) CENTROPTILUM BIFURCATUM McDUNNOUGH C e n t r o p t i l u m b i f u r c a t u m McDunnouqh, Needham, 1935, T n e B i o l o g y o f M a y f l i e s , 711 ( B i b l i o g r a p h y ) A d u l t : Thorax deep o l i v e brown, mesonotum w i t h a p a l e y e l l o w l i n e e x t e n d -i n g f o r w a r d along each l a t e r a l margin from the wing base, e n d i n g i n a s m a l l round y e l l o w i s h p a t c h , and y e l l o w i s h s u t u r e s and p o s t e r i o r m a r g i n ; l e g s p a l e y e l l o w i s h w h i t e , femora deeper i n c o l o u r ; wings h y a l i n e ; h i n d wing r e l a t i v e l y wide; two l o n g i t u d i n a l v e i n s , the second may be f a i n t l y f o r k e d near i t s apex; abdominal t e r g i t e s 2-6 h y a l i n e , y e l l o w i s h white; t e r g i t e s 2 r4 w i t h a f a i n t r e d d i s h d o r s a l h a i r - l i n e , and t r a c e s of ruddy s h a d i n g on p o s t e r i o r m a r g i n s ; on segments 2-6, s p i r a c u l a r a r e a marked by a broken b l a c k i s h l i n e ; -139-t e r g i t . e s 7-9 deep c h o c o l a t e brown; t e r g i t e 1.0 p a l e y e l l o w i s h ; s t e r n i t e s 7-9 a l a b a s t e r w h i t e ; f o r c e p s and t a i l s w h i t i s h ; p l a t e between f o r c e p s base l a r g e and dome-shaped; b e a r i n g a s m a l l p o i n t e d t u b e r c l e . Nymph: Unknown D i s t r i b u t i o n : Idaho, B r i t i s h Columbia No specimens o f t h i s s p e c i e s were examined. CENTROPTILUIYI CONTURBATUffl McDUNNOUGH C e n t r o p t i l u m conturbatum fflcDunnough, Needham, 1935, The B i o l o g y m a y f l i e s , 712 ( B i b l i o g r a p h y ) A d u l t : T u r b i n a t e eyes dark b l a c k i s h brown; t h o r a x s h i n y b l a c k ; l e g s w h i t e ; wings h y a l i n e ; v e n a t i o n p a l e ; abdominal t e r g i t e s 2-6 and p a r t of 7 h y a l i n e w h i t e , sometimes w i t h f a i n t dusky s h a d i n g p o s t e r -i o r l y on m i d d l e segments; t e r g i t e s 8-10, and o f t e n p a r t of 7, choco-l a t e brown; s t e r n i t e s w h i t e , 2-6 h y a l i n e , 7-10 opaque; t a i l s w h i t e ; i n n e r margin o f second f o r c e p s j o i n t d i s t i n c t l y t u b e r c u l a t e ; t h i r d j o i n t s t r o n g l y bowed; d i s t a l j o i n t u n u s u a l l y l o n g ; p l a t e between f o r c e p s base c o n i c a l on i t s p o s t e r i o r m a r g i n . Nymph: Unknown D i s t r i b u t i o n : Wyoming, C a l i f o r n i a , B r i t i s h C olumbia No specimens of t h i s s p e c i e s were examined. C e n t r o p t i l u m s p . 1 A d u l t : Unknown Nymph: P e c t i n a t e s p i n e s on g a l e a ; g i l l s s i n g l e on segments 1-7, l a r g e ; t r a c h e a t i o n i n d i s t i n c t ; abdominal t e r g i t e s brown, markings v a r i a b l e -140-u s u a l l y 3 p a l e s p o t s on each t e r g i t e , but. t h e r e may be fewer or none; t e r g i t e s 7 and 10, or 7 o n l y , or 1, 2, 6, 7, and 10, may be p a l e ; t a i l s 3, h e a v i l y f r i n g e d ; t a i l s u s u a l l y p a l e w i t h a dark m i d d l e and a p i c a l band or may be e n t i r e l y p a l e . E c o l o g y : T h i s s p e c i e s was t a k e n from the m i d d l e and edges of v a r i o u s l o c a t i o n s on the A l o u e t t e R i v e r , from depths r a n g i n g from 1 t o 5 f e e t , . g e n e r a l l y , however, a t depths of 1 to 2 f e e t . The stream bed v a r i e d from mud, t h r o u g h sand, g r a v e l , r o c k s and b o u l d e r s t o be d r o c k . The c u r r e n t was a l s o v a r i a b l e , from q u i e t , s t i l l w a t e r , to s w i f t r a p i d s . T h i s i s a v e r y p l e n t i f u l and common s p e c i e s . They were t a k e n the y e a r round. D i s t r i b u t i o n ; B r i t i s h Columbia M a t e r i a l Examined; 3 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), V.14.59 (N.3. F i l m e r ) , 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), V I I I . 2 6 . 5 9 (N.3. F i l m e r ) , 2 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), XI.26.59, (N.3. F i l m e r ) . C e n t r o p t i l u m sp. 2 A d u l t : Unknown Nymph: M a x i l l a r y p a l p 2 - j o i n t e d ; s l i g h t s p i n e s on p o s t e r o - l a t e r a l a n g l e s of a b dominal t e r g i t e s ; g i l l s l a r g e , on segments 1-7, d i s t i n c t l y t r a c h e a t e d ; g i l l s on segments 1-2 d o u b l e , r e s t s i n g l e ; l a t e r a l margins of a l l abdominal t e r g i t e s p a l e , each margin w i t h a brown t r a n s v e r s e band; t e r g i t e s 7-10 l a r g e l y shaded w i t h brown; t a i l s 3, e n t i r e l y p a l e . -141-E c o l o q y : T h i s s p e c i e s mas t a k e n from o n l y one l o c a t i o n on the A l o u e t t e R i v e r , from the edge, a t a depth o f 1 t o 2 f e e t . The stream bed c o n s i s t e d of mud and s i l t , w i t h some r o c k s . The water was s t i l l . A l l specimens were t a k e n i n mid-August. D i s t r i b u t i o n : B r i t i s h Columbia M a t e r i a l Examined: 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), V I I I . 1 1 . 5 9 (N.3. F i l m e r ) ; 9 Nymphs, B r i t i s h C o l u m b i a : S p r i n g h o u s e Lake, V I I I . 3 1 . 5 2 (G.G.E. S c u d d e r ) . C e n t r o p t i l u m s p . 3 A d u l t : Unknown Nymph: Both m a n d i b l e s e q u a l i n s i z e ; g i l l s double on segment 1 and 2, s i n g l e on segments 3-7; abdominal t e r g i t e s w i t h a f a i n t p a t t e r n , but p o s t e r i o r b o r d e r s dark brown; t a i l s e n t i r e l y p a l e . D i s t r i b u t i o n : B r i t i s h Columbia M a t e r i a l Examined: 7 Nymphs, B r i t i s h C o l u m b i a : Babine Lake, VII.10.61 (T. N o r t h c o t e ) . C e n t r o p t i l u m sp. 4 A d u l t : Unknown Nymph: M a n d i b l e s e q u a l i n s i z e ; g i l l s double on segments 1 and 2, s i n g l e on segments 3 t o 7; abdominal t e r g i t e s and s t e r n i t e s u n i c o l o u r e d , brown, w i t h no p a t t e r n ; t a i l s 3, e n t i r e l y p a l e . D i s t r i b u t i o n : B r i t i s h Columbia -142-l Y I a t e r i a l Examined: 1 Nymph, 8 r i t i s h C o l u m b i a : S p r i n g h o u s e Lake, V I I I . 1 8 ; 6 2 (G.G.E. S c u d d e r ) , 1 Nymph, B r i t i s h C o l u m b i a : UJestu/ick, VI.1.62 (G.G.E. S c u d d e r ) . GENUS i-NEGCLOEQN TRAVER '\u00E2\u0080\u00A2^NaQcloeon, Needham, 1935, The B i o l o g y o f M a y f l i e s , 730 ( B i b l i o g r a p h y ) A d u l t : S m a l l m a y f l i e s ; t u r b i n a t e eyes l a r g e , l e n g t h i l y egg-shaped; eyes o f female l a r g e and s e t h i g h on the s i d e o f the head; p o s t e r i o r margin o f head v e r y s l i g h t l y e m a r g i n a t e ; f o r e l e g of male s l i g h t l y s h o r t e r t h a n the body; femur 3/4 the l e n g t h o f the t i b i a , which i s s u b e q u a l t o the t a r s u s ; i n f e m a l e , femur and t i b i a s u b e q u a l ; t i b i a about 1-1/2 as l o n g as t a r s u s ; i n h i n d l e g of male, femur 1-1/3 t o 1-1/2 t i m e s t h e l e n g t h of the t i b i a , which i s s u b e q u a l to the t a r s u s ; b a s a l t a r s a l j o i n t o f both sexes v e r y l o n g , e q u a l t o o t h e r 3 j o i n t s combined; i n h i n d l e g of f e m a l e , femur al m o s t t w i c e the l e n g t h o f the t i b i a , which i s s l i g h t l y l a r g e r than the t a r s u s ; m a r g i n a l i n t e r c a l a r i e s o f f o r e w i n g s i n g l e ; h i n d wing a b s e n t ; b a s a l j o i n t of f o r c e p s 1-1/3 tim e s as wide as l o n g ; 2nd j o i n t s h o r t and b r o a d , i t s i n n e r margin w i t h a p r o m i n e n t , axe-shaped e x t e n s i o n ; s l i g h t s w e l l i n g near base on i n n e r margin of 3rd j o i n t ; and a more d i s t i n c t s w e l l i n g a p i c a l l y , t h e whole b e i n g s l i g h t l y bowed; d i s t a l j o i n t 2- 1/2 t o 3 t i m e s as l o n g as wide; a p i c a l margin o f s t e r n i t e 9 o f female a l m o s t s t r a i g h t . Nymph: M a x i l l a r y p a l p i 3 - j o i n t e d , e x t e n d i n g w e l l beyond t o t i p o f the g a l e a - l a c i n i a ; c a n i n e s o f m a n d i b l e s l o n g and s l e n d e r ; l a b i a l p a l p i 3- j o i n t e d , d i s t a l j o i n t s w i d e l y d i l a t e d a p i c a l l y ; c l a w s l o n g and -143-s l e n d e r ; almost 3/4 as l o n g as the t a r s i , not d e n t i c u l a t e ; meta-t h o r a c i c wing buds a b s e n t ; g i l l s s i n g l e on segments 1-7; g i l l s a s s y m e t r i c a l l y shaped, s t r a i g h t on a n t e r i o r margin and l o b e d on p o s t e r i o r m a r g i n ; t r a c h e a t i o n p i n n a t e , a l l branches on the p o s t e r i o r s i d e ; t a i l s 3, a p p r o x i m a t e l y e q u a l i n l e n g t h and t h i c k n e s s . Genotype; ..'Neocloeon alamance T r a v e r . '\u00E2\u0080\u00A2\u00E2\u0080\u00A2'Mfi'n'r.loson s p . 1 A d u l t : Unknown Nymph: No p e c t i n a t e s p i n e s on g a l e a ; g i l l s s i n g l e on segments 1-7; a g e n e r a l l y p a l e s p e c i e s ; w i t h abdominal t e r g i t e 7 d a r k ; t a i l s e n t i r e l y p a l e , or w i t h a dark t i p . E c o l o g y ; Specimens o f t h i s s p e c i e s were t a k e n from t h e m i d d l e and edges o f many l o c a t i o n s on the A l o u e t t e R i v e r . The depth v a r i e d from l / 2 t o 5 f e e t , a l t h o u g h u s u a l l y the water was 1 f o o t deep. The stream bed v a r i e d from mud, through sand, g r a v e l , r o c k s , and b o u l d e r s , t o bedrock. The c u r r e n t was g e n e r a l l y s t i l l t o q u i e t r i p p l e s . Specimens were taken from May to December. M a t e r i a l Examined: 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), V.26.59 (N.3. F i l m e r ) , 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), V.19.59, (N.3. F i l m e r ) , 1 Nymph: B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), VI.9.59 (N.3. F i l m e r ) , 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), VII.1.59 (N.3. F i l m e r ) . -144-SUPERFAIYIILY LEPTQPHLEBIOIDEA Key To A d u l t s 1. H i n d wings a b s e n t . Outer f o r k o f Rs of f o r e w i n g v e r y deep. P o s t e r i o r branch o f IYI i n f o r e w i n g and i n t e r c a l a r y between branches o f t h i s v e i n much s h o r t e r than a n t e r i o r b r a n c h , not e x t e n d i n g t o base of wing. F o r c e p s 3 - j o i n t e d F a m i l y T r i c o r y t h i d a e , S u b f a m i l y L e p t o h y p h i n a e Hind wing p r e s e n t . Outer f o r k of Rs of f o r e w i n g n o r m a l . P o s t e r i o r b ranch o f IYI o f f o r e w i n g normal. F o r c e p s 1, 2, or 3 j o i n t e d . . .. 2. 2. No t r u e i n t e r c a l a r i e s i n f o r e w i n g between median i n t e r c a l a r y and p o s t e r i o r branch of IYI, or between Pil and C u l . Male f o r c e p s w i t h 2 or 3 s h o r t t e r m i n a l j o i n t s . F a m i l y L e p t o p h l e b i i d a e , S u b f a m i l y L e p t o p h l e b i i n a e Two s h o r t i n t e r c a l a r i e s i n f o r e w i n g between median i n t e r c a l a r y and p o s t e r i o r branch o f IYI, a l s o between IYI and C u l . lYIale f o r c e p s w i t h a s i n g l e s h o r t t e r m i n a l j o i n t . . . . . . . . . F a m i l y E p h e m e r e l l i d a e , S u b f a m i l y E p h e m e r e l l i n a e Key To Nymphs 1. G i l l s p r e s e n t on segments 1 to 7. No e l y t r o i d g i l l s . G i l l s t u n i n g - f o r k shaped, w i t h o u t f r i n g e d m a r g i n s . Depressed m a n d i b u l a r t u s k s v i s i b l e from above F a m i l y \u00E2\u0080\u00A2 L e p t o p h l e b i i d a e , S u b f a m i l y L e p t o p h l e b i i n a e G i l l s not on segments 1 to 7. lYlay o r may not be e l y t r o i d o r semi e l y t r o i d g i l l s . No m a n d i b u l a r t u s k s . 2. -145-2. ' G i l l s p r e s e n t on segment.3 or 4 to 7. G i l l s on segments 3 or 4 may be e l y t r o i d , semi e l y t r o i d , or s i m i l a r to t h o s e on segments 4 or 5 t o 7. A r u d i m e n t a r y g i l l i s o f t e n p r e s e n t on Segment 1 F a m i l y E p h e m e r e l l i d a e , S u b f a m i l y E p h e m e r e l l i n a e G i l l s p r e s e n t on segments 1 to 6 o n l y , r u d i m e n t a r y on segment 1. . G i l l s on Segment 2 e l y t r o i d ; t r i a n g u l a r o r o v a l , c o v e r i n g a l l o t h e r s F a m i l y T r i c o r y t h i d a e , S u b f a m i l y L e p t o h y p h i n a e SUBFAMILY LEPTOPHLEBIINAE A d u l t ; E y e s ' o f male not t u r b i n a t e j b u t -grooved;- h i n d femur u s u a l l y s h o r t e r than t i b i a , which .is l o n g e r than the t a r s u s ; t a r s i 4 - j o i n t e d y e x c e p t f o r a v e r y s h o r t e x t r a b a s a l j o i n t i n the male f o r e t a r s u s ; a l l c l a w s d i s s i m i l a r ; no t r u e i n t e r c a l a r i e s between t h e median i n t e r c a l a r y and\u00E2\u0080\u00A2the p o s t e r i o r branch of the media i n the f o r e w i n g , or between t h e p o s t e r i o r b r a n c h o f the media and the a n t e r i o r b ranch of the c u b i t u s ; the two branches of the c u b i t u s u s u a l l y s e p a r a t e d at base; between t h e s e two branches are 2 to 4 l o n g i n t e r c a l a r i e s ; Of of f o r e w i n g and p o s t e r i o r b r a n c h of the media n o r m a l , a t t a c h e d b a s a i l y ; f i r s t a n a l v e i n ends i n the h i n d m a r g i n , but not by a s e r i e s o f v e i n l e t s ; Of of h i n d wing a b s e n t ; c o s t a l p r o j e c t i o n p r e s e n t or a b s e n t ; f o r c e p s 3 - j o i n t e d , a l t h o u g h t h e r e i s o c c a s i o n a l l y a s m a l l f o u r t h a p i c a l j o i n t ; b a s a l j o i n t l o n g e r than 'any o t h e r ; s u b a n a l p l a t e of female w i t h a d e e p l y e x c a v a t e d median c l e f t ; t a i l s t h r e e . Nymph; May be d e p r e s s e d i n head and t h o r a x w i t h head p r o g n a t h o u s , or compressed, w i t h head, hypognathous; m a n d i b l e s o f t e n v i s i b l e d o r s a l l y ; may be d e p r e s s e d m a n d i b u l a r t u s k s , v i s i b l e d o r s a l l y ; l a b i a l p a l p i 3 - j o i n t e d ; a l l c l a w s s i m i l a r , d e n t i c u l a t e ; g i l l s p r e s e n t on segments -146-1-7; g i l l s f o r k e d , w i t h o u t f r i n g e d m a r g i n s , or w i t h o u t e r margins b e a r i n g l o n g f r i n g e s which are u n i t e d a t the base, o r t e r m i n a t i n g i n a f i l a m e n t or p o i n t ; p o s t e r o - l a t e r a l s p i n e s p r e s e n t on segments 8 and 9, or 9 o n l y ; t a i l s 3, the o u t e r t a i l s f r i n g e d on both s i d e s . SUBFAMILY LEPTOPHLEBIINAE Key To A d u l t s 1. M i d d l e t a i l s h o r t e r and weaker than l a t e r a l s B l a s t u r u s Eaton M i d d l e t a i l a p p r o x i m a t e l y e q u a l t o l a t e r a l s i n l e n g t h and t h i c k n e s s . ..2. 2. Penes s e p a r a t e d a l m o s t t o base. A l o n g f l a p - l i k e appendage, narrowed d i s t a l l y , i s a t t a c h e d near apex of each p e n i s and e x t e n d s i n w a r d and downward between l o b e s of penes..... L e p t o p h l e b i a iUestwood Penes not s e p a r a t e d a l m o s t t o base. U s u a l l y two s e t s o f appendages, an upper and s h o r t e r p a i r e x t e n d i n g l a t e r a l l y , and a l o n g e r p a i r ( t h e r e f l e x e d s p u r ) e x t e n d i n g backward, o f t e n o b l i q u e l y P a r a l e p t o p h l e b i a L e s t a g e Key To Nymphs 1. G i l l s b r o a d , not l o b e d , l a m e l l i f o r m . G i l l on segment 1 d i f f e r e n t from r e s t , b i f i d e x c e p t a t b ase...... B l a s t u r u s Eaton G i l l s l a n c e o l a t e , and t u n i n g - f o r k shaped. G i l l on segment 1 l i k e a l l the r e s t P a r a l e p t o p h l e b i a L e s t a g e GENUS LEPTOPHLEBIA UIESTUJOOD L e p t o p h l e b i a , Needham, 1935, The B i o l o g y of M a y f l i e s , 507 ( B i b l i o g r a p h y ) A d u l t : Male f o r e t a r s u s l o n g e r than t i b i a ; p o s t e r i o r branch o f Of o f Rs of f o r e w i n g sagged to r e a r w a r d ; h i n d wing w i t h no c o s t a l p r o j e c t i o n -147-but a s l i g h t c o n c a v i t y near the m i d d l e of the a n t e r i o r m a r g i n ; media of h i n d wing f o r k e d ; penes s e p a r a t e d a l m o s t to base; a l o n g , d i s t a l l y narrowed, f l a p - l i k e appendage ex t e n d s i n w a r d and downward from the apex of each p e n i s , r e a c h i n g between the l o b e s o f the penes; c l e f t i n the base of each f o r c e p s ; c l e f t i n a p i c a l margin of s u b a n a l p l a t e o f female deep; l o n g , a p p r o x i m a t e l y e q u a l i n l e n g t h and t h i c k n e s s . Nymph: Labrum much narrower than the head; 5-6 m a x i l l a r y s p i n e s ; 1 row o f t e e t h on c l a w s ; g i l l s b r o a d , l a n c e o l a t e , not f r i n g e d ; g i l l s on segment 1 b i f i d , e x c e p t at base, d i f f e r i n g i n form from f o l l o w i n g p a i r s ; no l a t e r a l l o b e s on bases of g i l l s ; t e r m i n a l e x t e n s i o n o f each g i l l . l o n g and s l e n d e r ; w e l l - d e v e l o p e d p o s t e r o - l a t e r a l ' s p i n e s on segments 8 and 9; p o s t e r i o r margins o f a l l a bdominal t e r g i t e s w i t h a dense row of minute s p i n u l e s . Genotype: L e p t o p h l e b i a v e s p e r t i n a ( i n Ephemera) L i n n a e u s LEPTOPHLEBIA ' Key To A d u l t s 1. S h i n y dark brown. C, Sc and R, brown, heavy, o t h e r v e i n s p a l e brown. S h o r t , s t o u t abdomen. D i s t i n c t c r o s s v e i n s between IY12 and Cu , s p . l S h i n y dark brown, but a n t e r i o r 1/4 of t e r g i t e s 2-7 p a l e h y a l i n e . Long, s l e n d e r abdomen. F a i n t c r o s s v e i n s between IYI2 and Cu. C, Sc and R, y e l l o w , heavy, o t h e r v e i n s p a l e sp. 2 L e p t o p h l e b i a s p . 1 A d u l t : A s h i n y dark brown s p e c i e s ; l e g s r e d d i s h y e l l o w , f o r e l e g s d a r k e r ; -148-C, Sc and R l heavy, dark brown, o t h e r v e i n s l i g h t brown. Nymph; Unknown D i s t r i b u t i o n : B r i t i s h Columbia M a t e r i a l Examined: 2 Female, B r i t i s h C o l u m b i a : G h i l c o t i n , VI.16.29, ( G . J . S p e n c e r ) , 2 subimagos, B r i t i s h C o l u m b i a : C h i l c o t i n , VI.15.29 ( G . J . S p e n c e r ) l . s u b i m a g o , B r i t i s h C o l u m b i a : Q u e s n e l , VII.16.49 ( G . J . S p e n c e r ) 1 subimago, B r i t i s h C o l u mbia: Q u e s n e l , VI.25.49 ( G . J . S p e n c e r ) 1 Female, B r i t i s h C o l u m b i a : P h i l i l l o a Lake, VI.6.60, (E.Adams). L e p t o p h l e b i a sp. 2 A d u l t : ( M a l e ) A s h i n y dark b r o w n ' s p e c i e s ; l e g s brown, t a r s i p a l e ; C, SC, R l of f o r e w i n g y e l l o w , heavy, o t h e r v e i n s p a l e ; f a i n t c r o s s v e i n s between M2 and Cu; a n t e r i o r l / 4 of abdominal t e r g i t e s 2-7 p a l e h y a l i n e ; t a i l s and f o r c e p s p a l e . . Nymph: Unknown D i s t r i b u t i o n ; B r i t i s h C olumbia M a t e r i a l Examined: 1 fflale, B r i t i s h C o l u m b i a : Haney, V I I . 7 . 4 8 , 1 Male, B r i t i s h C o l u m b i a : Haney, VII.5.48 1 fflale, B r i t i s h C o l u mbia: C h i l c o t i n , VI.16.29 ( G . J . S p e n c e r ) 1 male, B r i t i s h C o l u m b i a : C h i l c o t i n , VI.12.31 ( G . J . S p e n c e r ) 1 fflale, B r i t i s h Columbia;: D e p a r t u r e Bay, VI.10.25 ( G . J . Spencer) : 1 ?, B r i t i s h C o l u m b i a : Vancouver, VI.3.34 ( J . K . J a c o b ) , 1 subimago B r i t i s h C olumbia: Q u e s n e l , VI.25.49 .('G.J. S p e n c e r ) , 1 subimago . B r i t i s h C o l u mbia: Q u e s n e l , V I I I . 7 . 4 8 ( G . J . S p e n c e r ) . 1 ? K e t t l e V a l l e y , V I . - V I I I . 3 5 . -149-\u00E2\u0080\u00A2 GENUS BLASTURUS EATON B l a s t u r u s , Needham, 1935, The B i o l o g y of M a y f l i e s , 531 ( B i b l i o g r a p h y ) A d u l t ; L a r g e , brown, r e d d i s h - b r o w n , or b l a c k i s h m a y f l i e s ; f o r e l e g s d a r k , o t h e r s ; p a l e ; no bands on femora; knee caps n a r r o w l y c r o s s - l i n e d w i t h b l a c k ; wings s u b h y a l i n e ; may be c l o u d e d w i t h brown; u s u a l l y a l i t t l e d a r k e r toward the c o s t a ; numerous i r r e g u l a r and anastomosing s t i g m a t i c c r o s s v e i n s ; p o s t e r i o r branch of Of of Rs of f o r e w i n g sags t o r e a r w a r d ; h i n d wing w i t h no c o s t a l p r o j e c t i o n ; c o s t a l margin s l i g h t l y concave a t m i d d l e ; abdomen l i g h t e r i n c o l o u r than t h o r a x , e s p e c i a l l y i n m i d d l e segments, and p a l e r j o i n i n g s of segments g i v e abdomen an a n n u l a t e appearance; t e r g i t e s w i t h a p a l e narrow median l i n e , on each s i d e of which i s a p a i r of o b l i q u e p a l e marks i n a n t e r i o r p o r t i o n o f each t e r g i t e ; f o r c e p s 4 - j o i n t e d o c c a s i o n a l l y , o t h e r w i s e 3 - j o i n t e d ; penes l o n g , s e p a r a t e d by a U-shaped n o t c h ; a s m a l l a c u r v i n a t e s p i n e a t t i p of each p e n i s ; each p e n i s w i t h a l a r g e , f l a t t e n e d , c u r v e d r e f l e x e d s p u r which r e a c h e s t o the base o f the n o t c h ; s u b a n a l p l a t e o f female p r o l o n g e d and d e e p l y e m a r g i n a t e ; t a i l s t h r e e , m i d d l e one weaker and s h o r t e r than the l a t e r a l s , u s u a l l y d a r k e r a t j o i n i n g s . Nymph; Claws w i t h a double row of d e n t i c l e s ; g i l l s on segments 1-7, l a m e l l i f o r m , t h o s e of t h e m i d d l e segments w i t h one or two b l u n t l o b e s a t the bases of the t e r m i n a l e x t e n s i o n s ; t e r m i n a l e x t e n s i o n s v e r y l o n g and s l e n d e r ; g i l l on segment 1 not l i k e the r e s t , narrow, b i f i d e x c e p t a t base; g i l l l a m e l l a e wide, margins e n t i r e i n segments 1 and 7; i n r e s t t e r m i n a l f i l a m e n t d e e p l y notched on one or both s i d e s ; -150-p o s t e r o - l a t e r a l s p i n e s on t e r g i t e s 8 and 9; t a i l s 3, a l l much t h e same i n . l e n g t h and t h i c k n e s s . Genotype: B l a s t u r u s c u p i d u s ( i n Ephemera) Say BLASTURUS Key To A d u l t s 1. B r o w n i s h c l o u d e x t e n d i n g a c r o s s o u t e r t h i r d o f wing t i p . T a i l j o i n i n g s dark brown. M i d d l e t a i l l / 4 l e n g t h o f l a t e r a l t a i l s ..... n e b u l o s u s (UJalker) No c l o u d o r band on o u t e r p o r t i o n o f f o r e w i n g . T a i l j o i n i n g s dark brown or o b s c u r e . M i d d l e t a i l not l e s s t h a n l / 3 l e n g t h of the l a t e r a l t a i l s 2. 2. T a i l j o i n i n g s w h i t i s h , w i t h dark brown j o i n i n g s s p . 1 T a i l j o i n i n g s l i g h t or da r k , j o i n i n g s o b s c u r e 3. 3. T a i l s w h i t i s h to l i g h t t a n . Fore femur red-brown...cupidus (Say) T a i l s brown. Fore femur brown q r a u a s t e l l a (^-aton) Key To Nymphs 1. Upper p o r t i o n o f 3 r d p a i r of g i l l s w i t h a median e x t e n s i o n o f main t r a c h e a s h o r t e r than g i l l p l a t e p r o p e r . L a t e r a l l o b e s a t t i p of lower g i l l o f 3 r d p a i r a p p r o x i m a t e l y e q u a l i n l e n g t h . . . c u p i d u s (Say) Upper p o r t i o n of 3 r d p a i r of g i l l s w i t h a median e x t e n s i o n o f main t r a c h e a as l o n g as or l o n g e r t h a n g i l l p l a t e p r o p e r . L a t e r a l l o b e s on lo w e r p o r t i o n o f 3 r d p a i r unequal i n l e n g t h . . n e b u l o s u s (UJalker) Unknown: B l a s t u r u s q r a u a s t e l l a ( E a t o n ) -151-BLASTURU5 CUPIDU5 (SAY) B l a s t u r u s c u p i d u s ( S a y ) , Needham, 1935, The B i o l o g y of M a y f l i e s , 535 ( B i b l i o g r a p h y ) A d u l t : A b l a c k i s h s p e c i e s ; l e g s brown, f o r e femora d a r k e r red-brown w i t h n a r r o w l y b l a c k l i n e d knee c a p s ; wings s u b h y a l i n e , opaque; s t i g m a t i c a r e a s s t a i n e d brown; v e n a t i o n brown, d a r k e r i n s t i g m a t i c a r e a ; c r o s s v e i n s i n s t i g m a t i c a r e a i r r e g u l a r and a n a s t o m o s i n g ; abdominal t e r g i t e s dark brown becoming b l a c k i s h towards the ends; apex of 10th t e r g i t e y e l l o w i s h ; p a l e m i d - d o r s a l l i n e o b s c u r e or a b s e n t ; o b l i q u e p a i r e d s p o t s c r e s c e n t i c and may be s u f f u s e d w i t h b l a c k i s h , s p i r a c l e s marked by minute b l a c k e l o n g a t e dashes; s t e r n i t e s fawn c o l o u r ; s t e r n i t e 9 dark brown; t a i l s 3, m i d d l e t a i l l / 3 the l e n g t h o f the l a t e r a l s ; t a i l j o i n i n g s o b s c u r e l y brown, bands b e i n g a l t e r n a t e l y wide and narrow; penes as i n f i g . 3. Nymph: 6-7 l a r g e p e c t i n a t e s p i n e s below the crown of the m a x i l l a ; l e g s not banded, or w i t h i n d i s t i n c t bands; upper p o r t i o n o f the t h i r d p a i r o f g i l l s w i t h the median e x t e n s i o n o f the main t r a c h e a s h o r t e r than the g i l l p l a t e p r o p e r ; l a t e r a l l o b e s a t the t i p o f the lo w e r p o r t i o n s o f the 3 r d p a i r of g i l l s a p p r o x i m a t e l y e q u a l i n l e n g t h ; p o s t e r o - l a t e r a l s p i n e s on t e r g i t e B s h o r t e r t h a n t h o s e on t e r g i t e 9, which a re b l u n t , not e x t e n d i n g to the c e n t e r o f t e r g i t e 10. D i s t r i b u t i o n : New York, Ohio, M a s s a c h u s e t t s , B r i t i s h C o l u m b i a . No specimens of t h i s s p e c i e s were examined. -152-BLASTURU5 GRAUASTELLA (EATOIM) B l a s t u r u s q r a v a s t e l l a ( E a t o n ) , Needham, 1935, The B i o l o g y o f May-f l i e s , 537 ( B i b l i o g r a p h y ) \u00E2\u0080\u00A2 A d u l t : ffl dark s p e c i e s , l e g s brown; wings h y a l i n e , a brown s t a i n i n the s t i g m a t i c a r e a o f the f o r e w i n g ; v e n a t i o n y e l l o w i s h - b r o w n e x c e p t i n b a s a l p o r t i o n ; s t i g m a t i c c r o s s v e i n s r e g u l a r and opaque; abdominal t e r g i t e s brown, m i d d l e segments l i g h t e r w i t h p a l e r j o i n i n g s ; m i d - d o r s a l p a l e l i n e v e r y f a i n t , b r o a d l y d i l a t e d a t p o s t e r i o r margins o f m i d d l e segments; p a i r e d o b l i q u e s p o t s c b s c u r , l i n e a r , c o n f l u e n t a n t e r i o r l y w i t h p a l e j o i n i n g s ; s t e r n i t e s p a l e r , u n i c o l o u r e d ; . t a i l s 3, m i d d l e t a i l , l / 3 t o l / 2 the l e n g t h o f the l a t e r a l s ; t a i l s brown, o b s c u r e l y and u n i f o r m l y t i n g e d w i t h d a r k e r brown. Nymph: Unknown D i s t r i b u t i o n : C o l o r a d o , B r i t i s h Columbia No specimens of t h i s s p e c i e s were examined. BLASTURUS NEBULOSUS (UJALKER) B l a s t u r u s n e b u l o s u s ( U J a l k e r ) , Needham, 1935, The B i o l o g y o f M a y f l i e s , 538 ( B i b l i o g r a p h y ) A d u l t : A b r o w n i s h b l a c k s p e c i e s ; f o r e l e g s r e d d i s h brown, femora p a l e r ; m i d d l e and h i n d l e g s y e l l o w i s h ; wings h y a l i n e ; f o r e w i n g s w i t h a b r o w n i s h c l o u d e x t e n d i n g a c r o s s a p i c a l 1/3 of the wing; v e n a t i o n brown; c o s t a l c r o s s v e i n s f a i n t e x c e p t i n s t i g m a t i c a r e a where they are i r r e g u l a r , crowded, and s l i g h t l y a n a s t o m o s i n g ; abdominal t e r g i t e s brown, d a r k e r on segments 1, 2, 8 and 9; p a l e m i d - d o r s a l l i n e v e r y f i n e and p a r t l y i n t e r r u p t e d ; o b l i q u e mark c r e s c e n t i c , i s o l a t e d ; -153-j o i n i n g s of m i d d l e segments w h i t i s h ; s t e r n i t e s p a l e r ; t a i l s p a l e brown o r g r e y i s h , r i n g e d a t j o i n i n g s w i t h dark brown; t a i l s 3, m i d d l e on l / 4 the l e n g t h of the i a t e r a l s ; l o b e s of f o r c e p s base s e p a r a t e d by a s h a r p l y U-shaped c l e f t and w i t h s u b - t r u n c a t e a p i c e s ; penes s e p a r a t e d by a g o b l e t - s h a p e d c l e f t ; r e f l e x e d spur s t r o n g l y b e n t , d i l a t e d a t t i p , and e x t e n d i n g below the l e v e l of the c l e f t . Nymph: 6-7 p e c t i n a t e s p i n e s below the crown of the m a x i l l a ; l e g s not banded, or w i t h i n d i s t i n c t bands; upper p o r t i o n o f 3 r d p a i r of g i l l s w i t h the media e x t e n s i o n of the main t r a c h e a as l o n g as or l o n g e r than the g i l l p l a t e p r o p e r ; l a t e r a l l o b e s o f lower p o r t i o n o f 3 r d p a i r o f g i l l s u n e q u a l i n l e n g t h ; p o s t e r o - l a t e r a l s p i n e on t e r g i t e 8 s h o r t e r than t h a t on t e r g i t e 9. D i s t r i b u t i o n ; Maine, C o l o r a d o , Wyoming, New York, U i r g i n i a , B r i t i s h C o l u m b i a . M a t e r i a l Examined: The a u t h o r has examined 41 specimens, a l l m a l e s , from the f o l l o w i n g l o c a l i t i e s : B r i t i s h C o l u m b i a : N i c o l a Lk., U.21.44; N i c o l a , VI.21.44; N i c o l a , . VI.27.43; Lake La Hache, VI.8.47; N i c o l a , VI.19.46; N i c o l a , VI.27.46; N i c o l a , VI.21.46. A l l specimens were t a k e n by Mr. G.J. Spenc e r . B l a s t u r u s s p . 1 A d u l t : (Female) Very s i m i l a r to B. n e b u l o s u s ; no c l o u d on wing; f o r e femur r e d -brown; t a i l s w h i t i s h , t a i l j o i n i n g s d a r k . Nymph: . Unknown D i s t r i b u t i o n : B r i t i s h Columbia -154-f / i a t e r i a l Examined: 3 Female, B r i t i s h C o l u m b i a : Lac La Hache, VI.8.47 ( G . J . S p e n c e r ) '6 Female, B r i t i s h C o l u m b i a : N i c o l a , VI.27.43 ( G . J . S p e n c e r ) 5 Female, B r i t i s h C o l u m b i a : N i c o l a , VI.19.46 ( G . J . S p e n c e r ) 3 Female, B r i t i s h C o l u m b i a : N i c o l a , VI.21.44 ( G . J . Sp e n c e r ) T h i s i s p o s s i b l y the female of B l a s t u r u s n e b u l o s u s ( U J a l k e r ) . GENUS PARALEPTOPHLEBIA LESTAGE P a r a l e p t o p h l e b i a , Needham, 1935, The B i o l o g y o f M a y f l i e s , 510 ( B i b l i o g r a p h y ) A d u l t : A s m a l l t o medium-sized s p e c i e s , sexes d i f f e r e n t i n c o l o u r ; males w i t h b l a c k i s h head, t h o r a x , and t i p of abdomen; female r e d d i s h o r r e d d i s h brown; l e g s y e l l o w i s h o r b r o w n i s h , w i t h o u t banded femora; p o s t e r i o r branch of Of of Rs of f o r e w i n g sagged t o r e a r w a r d ; no c o s t a l p r o j e c t i o n on h i n d wing, and c o s t a l margin s l i g h t l y concave i n c e n t e r ; median v e i n f o r k e d ; no i n t e r c a l a r i e s i n c u b i t a l f o r k , or between c u b i t u s and media; wings h y a l i n e , may be t i n t e d w i t h amber; m i d d l e abdominal segments i n mala dark brown, o r w h i t i s h , w i t h o r w i t h o u t o b s c u r e b r o w n i s h m a r k i n g s ; penes w i t h one, u s u a l l y 2 p a i r s o f appendages, the upper o f a p i c a l p a i r s h o r t e r and e x t e n d i n g l a t e r a l l y , the lower p a i r l o n g e r r e f l e x e d s p u r s e x t e n d i n g backwards, o f t e n o b l i q u e l y ; penes not s e p a r a t e d a l m o s t to base; f o r c e p s u s u a l l y 3 - j o i n t e d , a l t h o u g h t h e r e may be a 4 t h j o i n t by the a d d i t i o n of a s h o r t b a s a l r i n g - l i k e j o i n t o r a t e r m i n a l j o i n t ; c l e f t i n base of f o r c e p s ; a p i c a l margin of s u b a n a l p l a t e of femal e w i t h a deep median c l e f t ; t a i l s t h r e e , e q u a l i n l e n g t h and t h i c k n e s s , s l i g h t l y l o n g e r than the body. -155-Nymph: Nymphs s l e n d e r , compressed, head may be somewhat d e p r e s s e d ; m o uthparts as i n B l a s t u r u s and L e p t o p h l e b i a ; labrum much narrower than head, w i t h a s h a l l o w i n d e n t a t i o n on a n t e r i o r b o r d e r ; 4-6 l a r g e p e c t i n a t e s p i n e s below crown of the m a x i l l a ; c l a w s s l e n d e r and p e c t i n a t e , one row o n l y ; g i l l s n a r r o w l y l a n c e o l a t e , t u n i n g f o r k - s h a p e d or more d e e p l y d i v i d e d , not f r i n g e d on m a r g i n s ; g i l l s not d i m i n i s h e d i n s i z e t o r e a r w a r d , 1 s t p a i r s i m i l a r t o o t h e r s ; s p i n u l e s p r e s e n t . on p o s t e r i o r margins o f abdominal t e r g i t e s 1-10; p o s t e r o - l a t e r a l s p i n e s on t e r g i t e s 8 and 9, or 9 o n l y , those on 9 not more th a n 1/4 the l e n g t h o f the segment. Genotype; P a r a l e p t o p h l e b i a c i n c t a ( i n L e p t o p h l e b i a ) Eaton PARALEPTOPHLEBIA \" Key To A d u l t s 1. Penes w i t h r e f l e x e d spur on p e n i s t i p 2. Penes w i t h no r e f l e x e d s p u r on p e n i s t i p . . . . . . .5. 2. Conspi c u o u s l o b e on b a s a l j o i n t of f o r c e p s 3. No c o n s p i c u o u s l o b e on b a s a l j o i n t o f f o r c e p s 4. 3. T i p s o f penes w i t h a p a i r o f c o n v e r g e n t wide l o b e s p r o j e c t i n g w i t h i n the a p i c a l n o t c h . Wing l e n g t h 10 mm. . b i c o r h u t a (McD) T i p s o f penes w i t h no l o b e s w i t h i n the a p i c a l n o t c h . Wing l e n g t h 8 mm .., d e b i l i s ( W a l k e r ) 4. M i d d l e abdominal t e r g i t e s p r e d o m i n a n t l y b r o w n . . . q r e g a l i s ( E a t o n ) M i d d l e abdominal t e r g i t e s w h o l l y w h i t e . . . . . v a c i v a ( E a t o n ) 5. M i d d l e abdominal t e r g i t e s c l o u d e d or b o r d e r e d w i t h b l a c k or brown, but p r e d o m i n a n t l y w h i t e . 6. M i d d l e abdominal t e r g i t e s p r e d o m i n a n t l y b r o w n . . r u f i v e n o s a ( E a t o n ) -156-'' 6. Penes w i t h a p i c a l t e e t h 7. Penes w i t h no a p i c a l t e e t h h e t e r o n e a (fflcD) 7. B l a c k t r a n s v e r s e dash . i n p o s t e r o - l a t e r a l c o r n e r s of t e r g i t e s 2-6, remainder of a p i c a l margin p a l e , p a l l i p e s (Hagen) E n t i r e a p i c a l m a r g i n of each m i d d l e abdominal t e r g i t e n a r r o w l y black' . t e m p o r a l i s (HflcD) Key To Nymphs 1. M a n d i b l e w i t h t u s k s , .2. M a n d i b l e w i t h no t u s k s 5. 2. M a n d i b l e w i t h t u s k l o n g e r than the head .3. fflandible w i t h t u s k not as l o n g as head 4. 3. M a n d i b u l a r tu s k more than t w i c e the l e n g t h of the body of the m a n d ible \u00E2\u0080\u00A2 \u00E2\u0080\u00A2 *sp. 3 M a n d i b u l a r t u s k o n l y s l i g h t l y l o n g e r than the body of the mandible...' .. . b i c o r n u t a (McD) 4. Antennae w i t h no dark m e d i a l band. Legs p a l e , b a r r e d w i t h d a r k e r brown d e b i l i s (UJalker) Antennae w i t h a dark m e d i a l band. Legs d a r k , w i t h p a l e a p i c a l t r a n s v e r s e bands on femora \u00C2\u00BBsp. 4 5. L a t e r a l branches on g i l l t r a c h e a e .6. No l a t e r a l branches on g i l l t r a c h e a e 8 6. Fore t i b i a e not marked w i t h dark margins 7 Fore t i b i a e marked w i t h a dark margin \u00E2\u0080\u00A2 sp. 2 7. O c c i p u t dark p a l l i p e s (Hagen) O c c i p u t p a l e .. .sp. 5 8.. A few m i d d l e a b d o m i n a l segments p a l e s p o t t e d . . . . q r e q a l i s ( E a t o n ) A l l a b dominal segments p a l e s p o t t e d . . . sp. 1 -157-Unknown: P a r a l e p t o p h l e b i a h e t e r o n e a (IYlcD) P a r a l e p t o p h l e b i a r u f i v e n o s a ( E a t o n ) P a r a l e p t o p h l e b i a t e m p o r a l i s (IYlcD) P a r a l e p t o p h l e b i a v a c i v a ( E a t o n ) PARALEPTOPHLEBIA BICORIMUTA (lYlcDUNNOUGH) P a r a l e p t o p h l e b i a b i c o r n u t a (McDunnough), Needham, 1935, The B i o l o g y of M a y f l i e s , 517 ( B i b l i o g r a p h y ) A d u l t : . Head and t h o r a x b l a c k i s h broiun, above, p a l e r b e n e a t h ; wings h y a l i n e , v e n a t i o n brown; c o s t a l c r o s s v e i n s o b s o l e t e e x c e p t i n s t i g m a t i c a r e a where they a r e numerous, l o n g , a s l a n t ; and may be f o r k e d ; abdominal t e r g i t e 1 dark brown, 2 l i g h t e r , 8 t o 10 red-brown, 3-7 w h i t e w i t h p o s t e r i o r h a l f c l o u d e d o r b o r d e r e d w i t h brown o r b l a c k ; s t e r n i t e 1 brown, 8 and p o s t e r i o r h a l f of 9 b r i g h t r e d d i s h brown, r e s t f a i n t l y t i n g e d w i t h brown; b a s a l j o i n t of f o r c e p s brown, r e s t w h i t e ; a c o n s p -i c u o u s d o r s a l l o b e on the b a s a l j o i n t of the f o r c e p s ; penes b r o a d l y s e p a r a t e d by a very wide U-shaped n o t c h ; penes d i l a t e d and t r u n c a t e d a t t i p ; a p a i r of l o n g f l a t l o b e s c o n v e r g i n g by t h e i r rounded ends w i t h the n o t c h a re a t t a c h e d t o the d o r s a l s i d e o f the penes j u s t b e f o r e t h e i r t i p s ; r e f l e x e d s p u r b i f i d , a l m o s t c r e s c e n t i c , a t t a c h e d by back of c r e s c e n t , o u t e r horn l o n g e r ; t a i l p a l e brown. Nymph: m a n d i b l e ' w i t h a f o r w a r d p r o j e c t i n g tusk t h a t i s l o n g e r than the head, and o n l y s l i g h t l y l o n g e r than the body o f the m a n d i b l e ; g i l l t r a c h e a e w i t h no or a few l a t e r a l b r a n c h e s . E c o l o g y : T h i s s p e c i e s was t a k e n from the m i d d l e and edges of v a r i o u s -158-l o c a t i o n s on the A l o u e t t e R i v e r , u s u a l l y a t a depth o f 1 to 2 f e e t a l t h o u g h they have a l s o been t a k e n a t a depth o f 5 f e e t . The stream bed v a r i e d from mud, th r o u g h sand, g r a v e l , r o c k s , b o u l d e r s , to bedr o c k . The c u r r e n t v a r i e d from slow and q u i e t to r i p p l e s . A l l . specimens were c o l l e c t e d d u r i n g the months of Dul y , August, and September. D i s t r i b u t i o n ; A l b e r t a , Montana, B r i t i s h C olumbia M a t e r i a l Examined; 3 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), V I I I . 1 1 . 5 9 (N.D. F i l m e r ) . i PARALEPTOPHLEBIA DEB I LIS. (UJALKER ) P a r a l e p t o p h l e b i a d e b i l i s ( U J a l k e r ) , Needham, 1935, The B i o l o g y o f M a y f l i e s , 519 ( B i b l i o g r a p h y ) A d u l t ; Head and t h o r a x a deep r i c h brown; wings h y a l i n e ; v e n a t i o n p a l e ; c o s t a l c r o s s v e i n s o b s o l e t e e x c e p t i n s t i g m a t i c a r e a where they a r e numerous, s i m p l e , c u r v e d , a s l a n t , and o b s o l e s c e n t a t s u b c o s t a l ends; abdominal t e r g i t e s 1 and 8-10 deep r i c h brown; t e r g i t e s 3-7 w h i t e , w i t h p o s t e r i o r margins b r o a d l y b o r d e r e d w i t h b r o w n i s h p u r p l e ; s p i r a c l e s marked w i t h a brown p o i n t and a round brown spot a n t e r i o r to each above t h e l a t e r a l margin of the t e r g i t e s ; g a n g l i a marked w i t h y e l l o w ; b a s a l j o i n t of f o r c e p s w i t h a l a r g e , v e n t r a l , l o b e - l i k e d i l a t i o n ; penes s e p a r a t e d by a U-shaped n o t c h ; t i p s of penes w i t h no l o b e w i t h i n the a p i c a l n o t c h , but penes d i l a t e d a t t i p s , and on the o u t e r s i d e o f each t i p t h e r e i s a r e c u r v e d l a t e r a l t o o t h ; r e f l e x e d spur t w i c e as l o n g as the depth o f the n o t c h , a r c u a t e , o u t c u r v i n g and a c u t e a t t i p ; t a i l s w h i t e . -159-Nymph: Head brown d o r s a l l y w i t h a dark v e r t e x ; antennae w i t h no dark m e d i a l band; m a n d i b l e s s m a l l , o n l y a s m a l l p o r t i o n v i s i b l e d o r s a l l y , t i p s not e x t e n d i n g beyond head; no m a n d i b u l a r t u s k ; m a x i l l a r y p a l p 3 - j o i n t e d , the 1 s t j o i n t e q u a l i n l e n g t h t o the o t h e r two t o g e t h e r ; l e g s p a l e , banded w i t h d a r k e r brown; m i d d l e abdominal t e r g i t e s p a l e s p o t t e d ; g i l l t r a c h e a e w i t h o u t c o n s p i c u o u s l a t e r a l b r a n c h e s ; p o s t e r o -l a t e r a l s p i n e s on t e r g i t e s 8 and 9. D i s t r i b u t i o n ; New York, P e n n s y l v a n i a , Ohio, A l b e r t a , Washington, B r i t i s h C o l u m b i a . M a t e r i a l Examined; 2 Nymphs, B r i t i s h C o l u m b i a : N i c o l a Creek (G.G.E. S c u d d e r ) . PARALEPTOPHLEBIA GREGALIS (EATON) P a r a l e p t o p h l e b i a g r e g a l i s ( E a t o n ) , S p i e t h , 1941, Ann. E n t . Soc. Amer. 34:94 ( B i b l i o g r a p h y ) A d u l t : . A r e d d i s h brown m a y f l y ; t h o r a x b l a c k i s h d o r s a l l y ; wings h y a l i n e ; v e n a t i o n p a l e , w i t h l o n g i t u d i n a l v e i n s and s t i g m a t i c c r o s s v e i n s t i n g e d w i t h brown; s t i g m a t i c c r o s s v e i n s 12 to 16 i n number, somewhat b r a n c h i n g , i r r e g u l a r ; a l l abdominal t e r g i t e s brown, d a r k e r a t j o i n i n g s o f m i d d l e segments; b a s a l j o i n t of f o r c e p s w i t h no b a s a l d i l a t i o n o r l o b e or s h o r t b a s a l s u b j o i n t , but i s c o n i c a l b a s a l l y , t h e n p a r a l l e l s i d e d f o r h a l f i t s l e n g t h , t h e n s l o w l y t a p e r i n g t o apex; 2nd j o i n t t w i c e as l o n g as the 3 r d j o i n t ; penes s e p a r a t e d by a broad U-shaped no t c h which i s a l m o s t c l o s e d by a p a i r of h y a l i n e , o b l o n g , b r o a d , f l a t , o b l i q u e l y c o n v e r g i n g l o b e s e x t e n d i n g f o r most of t h e i r l e n g t h -160-beyond the c h i t i n i z e d t i p , g i v i n g the n o t c h a f l a s k shape; apex of each p e n i s i s o b l i q u e l y t r u n c a t e , the s h o r t e x t e r n a l a n g l e e n d i n g i n a s h a r p backward t o o t h ; r e f l e x e d spur i s h y a l i n e , s e m i - e l l i p t i c a l w i t h a s t r a i g h t i s h e x t e r n a l margin and a convex i n t e r n a l m a r g i n , w i d e s t near base and g r a d u a l l y t a p e r i n g towards the a c u t e apex, i t s g r e a t e s t w i d t h not more than 1/3 i t s l e n g t h , a l i t t l e l o n g e r than the depth of the n o t c h ; l o b e s o f the d i v i d e d 10th s t e r n i t e b r o a d l y t r i a n g u l a r w i t h rounded ends; t a i l s d i n g y w h i t i s h , f e r r u g i n o u s b a s a i l y . Nymph: Head marked w i t h a w h i t e s p o t ; no m a n d i b u l a r t u s k s ; f o r e t i b i a e marked w i t h dark m a r g i n s ; a few m i d d l e abdominal t e r g i t e s p a l e s p o t t e d ; g i l l t r a c h e a e w i t h no l a t e r a l b r a n c h e s ; p o s t e r o - l a t e r a l s p i n e s on t e r g i t e s 8 and. 9. D i s t r i b u t i o n ; C a l i f o r n i a , B r i t i s h C olumbia No specimens of t h i s s p e c i e s were examined. PARALEPTOPHLEBIA HETERONEA (lYlcDUNNOUGH) P a r a l e p t o p h l e b i a h e t e r o n e a (lYlcDunnough), Needham, 1935, ^he B i o l o g y m a y f l i e s , 523 ( B i b l i o g r a p h y ) A d u l t : Head and t h o r a x r i c k r e d d i s h brown d o r s a l l y ; wings w h i t i s h ; no c o s t a l c r o s s v e i n s , e x c e p t f o r a few i r r e g u l a r ones i n the s t i g m a t i c a r e a ; b a s a l abdominal t e r g i t e s and t e r g i t e s 8-10 brown, r e s t w h i t i s h i n a n t e r i o r p o r t i o n s and brown or b l a c k i s h p o s t e r i o r l y , p o s t e r i o r band b e i n g w i d e s t on segments 4 and 5 and d i s a p p e a r i n g on 7; s p i r a c l e s b l a c k and c o n n e c t e d by a b l a c k broken l i n e ; b a s a l j o i n t of f o r c e p s w i t h no l o b e , but broad b a s a i l y , p a r a l l e l s i d e d to m i d d l e , t h e n -161-t a p e r i n g s t r o n g l y ; 3 r d j o i n t n e a r l y as .long as the 2nd, but much more s l e n d e r ; penes s e p a r a t e d by a U-shaped n o t c h ; penes notched on i n n e r and o u t e r margins near apex; no a p i c a l t e e t h o r r e f l e x e d s p u r s . Nymph: Unknown. D i s t r i b u t i o n : C o l o r a d o , A l b e r t a , B r i t i s h C o l u mbia. No specimens of t h i s s p e c i e s were examined. PARALEPTOPHLEBIA PALLIPES (HAGEN) P a r a l e p t o p h l e b i a p a l l i p e s (Hagen), Needham,1935, The B i o l o g y of May-f l i e s , 527 ( B i b l i o g r a p h y ) A d u l t : Head and t h o r a x b l a c k d o r s a l l y ; wings w h i t i s h , m i l k y a l o n g c o s t a l a r e a ; e s p e c i a l l y i n s t i g m a t i c a r e a ; s t i g m a t i c c r o s s v e i n s few i n number, o b s c u r e , s t r a i g h t , unbranched; extreme wing base t i n g e d w i t h brown; abdominal t e r g i t e 2 p a l e brown, 3-6 w h i t e w i t h t o u c h e s o f brown on p o s t e r i o r b o r d e r s , l a b i a l s p i r a c l e s , and a l s o on s p i r a c l e s ; t e r g i t e s 2-6 w i t h b l a c k t r a n s v e r s e dashes i n p o s t e r o - l a t e r a l c o r n e r s ; t e r g i t e s 7-10 brown; g a n g l i a y e l l o w ; b a s a l f o r c e p s j o i n t w i t h no l o b e , but i s i r r e g u l a r l y t a p e r e d t o i t s a p i c a l 4 t h and then s l i g h t l y widened; 3 r d j o i n t a l m o s t as l o n g as the 2nd but much more s l e n d e r ; penes s e p a r a t e d by a g o b l e t - s h a p e d n o t c h ; penes c o n s i s t o f l o n g s l e n d e r t u b e s b e h i n d each of which i s a l o n g , s harp p o s t e r i o r l y d i r e c t e d , c u r v i n g s p i n e on the o u t e r s i d e of e a c h , i t s l e n g t h more than h a l f the depth of the n o t c h ; penes w i t h a p i c a l t e e t h but no r e f l e x e d s p u r s . Nymph: Head marked w i t h a dark o c c i p u t ; no m a n d i b u l a r t u s k s ; f o r e t i b i a e not marked w i t h dark m a r g i n s ; g i l l t r a c h e a e w i t h l a t e r a l b r a n c h e s ; m i d d l e abdominal t e r g i t e s p a l e s p o t t e d . -162-D i s t r i b u t i o n : Oregon, C o l o r a d o , C a l i f o r n i a , B r i t i s h Columbia No specimens of t h i s s p e c i e s were examined. PARALEPTOPHLEBIA RUFIUENOSA (EATON) P a r a l e p t o p h l e b i a r u f i v e n o s a ( E a t o n ) , S p i e t h , 1941, Ann. E n t . 5oc. Amer., 34:96 ( B i b l i o g r a p h y ) A d u l t : Head and t h o r a x dark brown; wings s u b h y a l i n e ; v e n a t i o n r e d d i s h , c r o s s v e i n s p a l e r e x c e p t i n b a s a l l / 3 ; s t i g m a t i c c r o s s v e i n s s t r o n g l y t i n g e d , crowded, o b l i q u e , some f o r k e d ; m i d d l e abdominal segments p a l e brown, a p i c a l segments dark brown; no p a t t e r n on t e r g i t e s ; s t e r n i t e 9 n a r r o w l y d i v i d e d by a U-shaped n o t c h ; b a s a l f o r c e p s j o i n t w i t h no c o n s p i c u o u s l o b e , no b a s a l d i l a t i o n , and not marked o f f by a s h o r t b a s a l s u b j o i n t , but t a p e r s r e g u l a r l y t o apex, s l i g h t l y c o r r u g a t e d i n t e r n a l l y ; 3 r d segment as l a r g e as the 2nd; penes s e p a r a t e d i n t h e i r a p i c a l h a l v e s by a rounded U-shaped n o t c h ; margins o f penes p a r a l l e l a l m o s t to t i p where t h e r e i s a l a t e r a l l y p r o j e c t i n g t r i a n g u l a r t o o t h on each; no a p i c a l t e e t h or r e f l e x e d s p u r s on penes; t a i l s p a l e brown. Nymph: Unknown D i s t r i b u t i o n : Idaho, B r i t i s h Columbia No specimens of t h i s s p e c i e s were examined. PARALEPTOPHLEBIA TEMPORALIS (lYlcDUNNOUGH) P a r a l e p t o p h l e b i a t e m p o r a l i s (lYlcDunnough), Needham, 1935, The B i o l o g y of M a y f l i e s , 529 ( B i b l i o g r a p h y ) A d u l t : Head and t h o r a x brown d o r s a l l y ; wings s u b h y a l i n e ; v e n a t i o n p a l e brown; c o s t a l c r o s s v e i n s n e a r l y o b s o l e t e ; s t i g m a t i c c r o s s v e i n s s i n g l e , s t r a i g h t , w e l l spaced a p a r t ; abdominal t e r g i t e s 2\u00E2\u0080\u00947 w h i t e w i t h -163-d i f f u s e and i l l - d e f i n e d narrow br o w n i s h or b l a c k i s h p o s t e r i o r m a r g i n s , d a r k e r on 2 and 7; s p i r a c l e s marked w i t h a b l a c k R-shaped mark e x t e n d -i n g back over the p o s t e r i o r - l a t e r a l c o r n e r ; b a s a l j o i n t o f f o r c e p s w i t h no c o n s p i c u o u s l o b e , but t a p e r e d t o 3/4 i t s l e n g t h ; penes d i v i d e d by a wide U-shaped n o t c h ; penes c o n s i s t o f l o n g , s t r a i g h t t u b e s on the o u t s i d e of which i s a l o n g s p i r a l l y t w i s t e d s p i n e , l y i n g i n the same p l a n e and as l o n g as the penes; penes w i t h a p i c a l t e e t h but no r e f l e x e d s p u r s . Nymph: Unknown D i s t r i b u t i o n : Oregon, B r i t i s h Columbia No specimens, of t h i s s p e c i e s were examined. PARALEPTOPHLEBIA UACIUA (EATON) P a r a l e p t o p h l e b i a v a c i v a ( E a t o n ) , S p i e t h , 1941, Ann. E n t . Soc. Amer. 34:96 A d u l t : Head and t h o r a x s h i n i n g b r o w n i s h b l a c k ; wings s u b h y a l i n e , f a i n t l y t i n g e d ; v e n a t i o n p a l e , but c o s t a l l o n g i t u d i n a l v e i n s and s t i g m a t i c c r o s s v e i n s p a l e ; s t i g m a t i c c r o s s v e i n s r e g u l a r and w i d e l y spaced; a b d o m i n a l segment 1 b l a c k , 2-7 t r a n s l u c e n t w h i t e w i t h f a i n t m i d - d o r s a l c l o u d s which a r e d a r k e r o n ' t e r g i t e 6 and s p r e a d d i f f u s e l y over more than h a l f o f t e r g i t e 7; t e r g i t e s 8-10 b l a c k i s h ; g a n g l i a marked w i t h brown, s t e r n i t e s 8-10 b r o w n i s h , no dark marks on s p i r a c l e s ; b a s a l f o r c e p s j o i n t w i t h no c o n s p i c u o u s l o b e ; penes l o n g , s e p a r a t e d by a narrow c l e f t ; penes t a p e r e d i n b a s a l h a l f , then i r r e g u l a r l y c y l i n d r i c a l ; on o u t e r margin of each p e n i s i s a v i s o r - l i k e b a c k w a r d - d i r e c t e d r e f l e x e d spur h a l f t h e i r own l e n g t h from the t i p ; t a i l s w h i t i s h . -164-Nymph: Unknown D i s t r i b u t i o n : Oregon, B r i t i s h C olumbia No specimens of t h i s s p e c i e s were examined. P a r a l e p t o p h l e b i a sp. 1 A d u l t : Unknown Nymph: A s h o r t , wide s p e c i e s ; no m a n d i b u l a r t u s k s ; each abdominal t e r g i t e w i t h a p a i r of s u b l a t e r a l dark d o t s ; g i l l s v e r y l o n g , t u n i n g - f o r k shaped; no l a t e r a l branches on g i l l t r a c h e a e ; p o s t e r o -l a t e r a l s p i n e s on t e r g i t e 9 l / 4 the l e n g t h o f the segment; a l l a b dominal t e r g i t e s p a l e s p o t t e d . E c o l o g y : T h i s s p e c i e s was c o l l e c t e d from many l o c a l i t i e s on the A l o u e t t e R i v e r , both from the m i d d l e and edges. . They have been found a t depths of 1 f o o t t o 5 f e e t , a l t h o u g h g e n e r a l l y a t 1 f o o t . The stream bed v a r i e d from mud, th r o u g h sand, g r a v e l , r o c k s and b o u l d e r s , t o b e d r o c k , .and the c u r r e n t from s l o w , q u i e t water to s w i f t r i p p l e s and r a p i d s . A l l specimens were t a k e n from dune to the f o l l o w i n g F e b r u a r y . D i s t r i b u t i o n : B r i t i s h Columbia M a t e r i a l Examined: 3 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), V I I I . 5 . 5 9 ( N . J . F i l m e r ) P a r a l e p t o p h l e b i a sp. 2 A d u l t : Unknown \u00E2\u0080\u00A2 Nymph: Longer and narrower than P a r a l e p t o p h l e b i a sp. 1; no m a n d i b u l a r -165-t u s k s ; l o n g t u n i n g - f o r k shaped g i l l s ; l a t e r a l branches on g i l l t r a c h e a e ; no s p o t s on t e r g i t e s ; p o s t e r o - l a t e r a l s p i n e s on t e r g i t e 9 l / 4 the l e n g t h of the segment; f o r e t i b i a e marked w i t h a dark m a r g i n . E c o l o g y : These nymphs were found i n s i t u a t i o n s i d e n t i c a l to t h o s e i n which P a r a l e p t o p h l e b i a s p . 1 were found, and were j u s t as common. They were c o l l e c t e d , however, o n l y d u r i n g Way, Dune, D u l y , and October to F e b r u a r y . D i s t r i b u t i o n : B r i t i s h C olumbia M a t e r i a l Examined: 3 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), VI.16.59 (N.D. F i l m e r ) P a r a l e p t o p h l e b i a sp. 3 A d u l t T Unknown Nymph: M a n d i b u l a r t u s k l o n g e r than the head, and more tha n t w i c e the l e n g t h o f the body of the m a n d i b l e ; femora each w i t h a p a l e a p i c a l t r a n s v e r s e band; g i l l t r a c h e a e w i t h no l a t e r a l b r a n c h e s . D i s t r i b u t i o n : B r i t i s h C o l umbia M a t e r i a l Examined: 13 Nymphs, B r i t i s h C o l u m b i a : N i c o l a Creek (G.G.E. Scud d e r ) P a r a l e p t o p h l e b i a sp. 4 A d u l t : Unknown Nymph: M a n d i b u l a r , t u s k not as l o n g as the head, about as l o n g as the body of frie m a n d i b l e ; antennae w i t h a dark m e d i a l band; l e g s d a r k , -166-femora each w i t h a p a l e a p i c a l t r a n s v e r s e band; no v i s i b l e t r a c h e a e i n g i l l s . D i s t r i b u t i o n ; B r i t i s h Columbia M a t e r i a l Examined: 4 Nymphs, B r i t i s h C o l u m b i a : N i c o l a Creek (G.G.E. S c u d d e r ) P a r a l e p t o p h l e b i a sp. 5 A d u l t : Unknown Nymph: O c c i p u t p a l e ; p a l e s p o t between a n t e n n a l bases and one l a t e r a l to each o c e l l u s ; no m a n d i b u l a r t u s k s ; mandible not v i s i b l e d o r s a l l y ; f o r e t i b i a e not marked w i t h dark m a r g i n s ; g i l l t r a c h e a e w i t h l a t e r a l b r a n c h e s . D i s t r i b u t i o n : B r i t i s h C olumbia M a t e r i a l Examined: 12 Nymphs, B r i t i s h C o l u m b i a : Loon Creek ( C l i n t o n ) , V.19.59 (G.G.E. S c u d d e r ) ; 5 Nymphs, B r i t i s h C o l u m b i a : Loon Creek ( C l i n t o n ) VI.13.? (H. L o r z ) . SUBFAMILY EPHEMERELLINAE A d u l t ; Eyes o f male not t u r b i n a t e , but are grooved; t a r s i 4 - j o i n t e d , e x c e p t the f o r a t a r s u s o f male which has a s h o r t b a s a l j o i n t ; a l l c l a w s d i s s i m i l a r ; v e n a t i o n o f f o r e w i n g s i m i l a r t o t h a t i n B l a s t u r u s ; 2 or more s h o r t f r e e i n t e r c a l a r i e s between the median i n t e r c a l a r y and the p o s t e r i o r branch of the M, and a l s o between the l a t t e r and CU1; 2 c u b i t a l i n t e r c a l a r i e s ; Of and the p o s t e r i o r b ranch of the ffl normal and a t t a c h e d b a s a l l y ; p o s t e r i o r b ranch of the Of of the Rs -167-not sagged t o r e a r w a r d ; Cu2 s t r o n g l y a n g u l a t e b e f o r e t he m i d d l e ; 1 s t a n a l v e i n ends i n the h i n d m a r g i n , but not by a s e r i e s o f v e i n l e t s ; h i n d wing w e l l d e v e l o p e d ; c o s t a l p r o j e c t i o n low; Of of Rs w a n t i n g ; f o r c e p s w i t h a s i n g l e s h o r t t e r m i n a l j o i n t ; t a i l s t h r e e . Nymph: No m a n d i b u l a r t u s k s ; p a i r e d s p i n e s o f t e n p r e s e n t d o r s a l l y on head, t h o r a x , and/or abdomen; f o r e l e g s w i t h a s p a r s e row of s e t a e on the i n n e r s u r f a c e s ; a l l c l a w s s i m i l a r ; no g i l l t u f t s on m a x i l l a e or f o r e coxae; g i l l s exposed, p r e s e n t on segments 3r7 o r 4-7; a r u d i m e n t a r y g i l l i s o f t e n p r e s e n t on segment 1; g i l l s on segments 3 or 4 may be s i m i l a r to the f o l l o w i n g g i l l s , o r may be e l y t r o i d o r s e m i - e l y t r o i d ; t a i l s t h r e e , a l l f r i n g e d on both s i d e s . GENUS EPHEMERELLA WALSH E p h e m e r e l l a , Needham, 1935, The B i o l o g y of M a y f l i e s , 562 Edmunds & A l l e n , 1959, Ann. E n t . Soc. Amer,, 52:543-546 ( B i b l i o g r a p h y ) A d u l t : S m a l l to medium s i z e d , u s u a l l y brownish m a y f l i e s ; eyes o f male d i v i d e d , s m a l l e r l o w e r p o r t i o n d a r k e r - t h a n the l a r g e r upper p o r t i o n ; eyes u s u a l l y c l o s e l y a p p r o x i m a t e d a p i c a l l y ; eyes o f female s m a l l e r , not d i v i d e d , w e l l s e t out on. the s i d e s o f the head; o c c i p i t a l margin s t r a i g h t between the eyes; pronotum u s u a l l y w i t h a median c a r i n a ; h i n d t a r s u s s h o r t e r than the t i b i a ; 2nd and 3rd t a r s a l j o i n t s sub-e q u a l ; h i n d wing w i t h a s l i g h t rounded c o s t a l p r o j e c t i o n , beyond which i s a v e r y s h a l l o w d e p r e s s i o n i n the c o s t a l m a r g i n ; IYI o f h i n d wing f o r k e d s l i g h t l y l e s s than h a l f w a y from base; f o r c e p s 3 - j o i n t e d , -168-the 2nd j o i n t b e i n g the l o n g e s t ; penes w i t h or w i t h o u t minute s p i n e s ; a p i c a l margin o f f o r c e p s base e n t i r e ; a p i c a l margin o f s u b a n a l p l a t e of female u s u a l l y o b t u s e l y rounded, but may be e m a r g i n a t e . A l l e n and Edmunds (Edmunds, 1959), i n t h e i r r e v i s i o n of the genus E p h e m e r e l l a , have d i v i d e d t h i s genus i n t o a number of subgenera, of which n i n e a re found i n N o r t h America. Of t h e s e , f i v e a r e r e p -r e s e n t e d t o date i n B r i t i s h C o l u mbia. T h e i r d i s t i n g u i s h i n g c h a r a c t e r i s t i c s a r e as f o l l o w s : Subgenus C a u d a t e l l a Edmunds (Male) L a t e r a l t a i l s l / 4 to 3/4 as l o n g as the median t a i l . Genotype: E p h e m e r e l l a h e t e r o c a u d a t a McD Subgenus P r u n e l l a Needham ( M a l e ) Inner margin of 2nd j o i n t of f o r c e p s d i s t i n c t l y i n c u r v e d o r s t r o n g l y bowed; t e r m i n a l segment of f o r c e p s more than t w i c e as l o n g as wide, but l e s s than 4 t i m e s as l o n g ; a l l t a i l s s u b e q u a l . Genotype: E p h e m e r e l l a d o d d s i Needham Subgenus S e r r a t e l l a Edmunds (M a l e ) P o s t e r o - l a t e r a l s p i n e s on segments 8 and 9 p o o r l y d e v e l o p e d or w a n t i n g ; t e r m i n a l j o i n t o f f o r c e p s l e s s t h a n t w i c e as l o n g as wide; penes e i t h e r w i t h d o r s a l o r v e n t r a l s p i n e s o r s u b a p i c a l t u b e r c l e s , the a p i c a l notch- deep, or penes as wide or w i d e r a t apex than a t base; p e n i s l o b e s u s u a l l y b e a r i n g a s u b a p i c a l l a t e r a l t u b e r c l e on each l o b e , i f l a c k i n g , no t u b e r c l e p r e s e n t between f o r c e p s b a s e s ; a l l t a i l s s u b e q u a l . Genotype: E p h e m e r e l l a s e r r a t a Morgan Subgenus Timpanoqa Needham (M a l e ) V e s t i g i a l g i l l s on abdominal segments 4-7; w s l l - d e v e l o p e d p o s t e r o - l a t e r a l s p i n e s on t e r g i t e s 8 and 9; t e r m i n a l segment of -169-f o r c e p s l e s s than t u i i c e as l o n g as broad; a l l t a i l s s u b e q u a l i n l e n g t h . Genotype; .Ephemerella hecuba Eaton Nymph; . . There i s a g r e a t v a r i a t i o n i n form i n t h e s e nymphs; some a r e s l e n d e r and s t r e a m l i n e d , and o t h e r s a r e f l a t t e n e d v e n t r a l l y and convex d o r s a l l y , w i t h broad f l a t t e n e d femora; some bear d o r s a l t u b e r c l e s or p a i r e d s p i n e s on the head, t h o r a x , abdomen, and l e g s ; some a r e smooth, and o t h e r s d e n s e l y c o v e r e d w i t h h a i r s ; labrum i s w i d e r than l o n g ; no m a n d i b u l a r t u s k s ; m a x i l l a e c o n i c a l a t a p i c e s , w i t h one o r more broad t e r m i n a l s p i n e s ; m a x i l l a r y p a l p i r u d i m e n t a r y or w a n t i n g , at most as l o n g as g a l e a - l a c i n i a ; l a b i a l p a l p i s h o r t ; no g i l l t u f t s on m a x i l l a e or f o r e coxae; no s e t a e on a n t e r o - l a t e r a l a n g l e s of the head; f o r e l e g s w i t h o u t a dense row of s e t a e on i n n e r s u r f a c e s ; t a r s a l c l a w s u s u a l l y d e n t i c u l a t e ; a bdominal t e r g i t e s u s u a l l y have l a t e r a l e x t e n s i o n s b e a r i n g p o s t e r o - l a t e r a l s p i n e s ; g i l l s exposed, d o r s a l i n p o s i t i o n ; i f g i l l on segment 4 i s f u l l y o p e r c u l a t e , t h e r e i s u s u a l l y a s h o r t g i l l r u d i m e n t on segment 1; t a i l s u s u a l l y as l o n g as the body, o f t e n h a i r y , or w i t h w h o r l s of s p i n e s at the j o i n i n g s , o f t e n h e l d u p r i g h t o r a r c h e d o v e r the abdomen; the d i s t i n g u i s h i n g c h a r a c t e r i s t i c of the B r i t i s h C olumbia subgenera a r e as f o l l o w s : Subgenus C a u d a t e l l a Edmunds G i l l s on abdominal segments 3-7; l a t e r a l t a i l s l / 4 t o 3/4 as l o n g as the median t a i l . Subgenus P r u n e l l a Needham D i s t i n c t t u b e r c l e s and/or s p i n e s u s u a l l y p r e s e n t on the a n t e r i o r -170-m argins of the f o r e femora; i f a b s e n t , the abdomen b e a r s an a d h e s i v e d i s c o f h a i r s v e n t r a l l y , ' o r the head, t h o r a x , and abdomen bear d i s t i n c t p a i r e d d o r s a l s p i n e s ; g i l l s on abdominal segments 3-7; a l l t a i l s s u b e q u a l i n l e n g t h . Subgenus E u r y l o p h e l l a T i e n s u u No m a x i l l a r y p a l p i ; t a r s a l c l a w s d e n t i c u l a t e ; p a i r e d abdominal t u b e r c l e s on t e r g i t e s 1-3 b l u n t ; l a m e l l a t e g i l l s on abdominal segments 4-7, the g i l l s on segment 4 s e m i - o p e r c u l a t e ; r u d i m e n t a r y g i l l s on segment 1; abdominal segment 9 l o n g e r than segment 8. Subgenus S e r r a t e l l a Edmunds No p a i r e d d o r s a l s p i n e s on head and t h o r a x , but they a re u s u a l l y p r e s e n t on the abdomen; d i s t i n c t t u b e r c l e s o r s p i n e s a b s e nt on a n t e r i o r margins of f o r e femora; abdomen w i t h no a d h e s i v e d i s c ; g i l l s on abdominal segments 3-7; g i l l s i m b r i c a t e ; g i l l on segment 3 not o p e r c u l a t e or s e m i - o p e r c u l a t e ; t a i l s s u b e q u a l i n l e n g t h , a w h o r l of s p i n e s o r h a i r - l i k e s p i n e s a t j o i n i n g s o f the segments of the median t a i l . Subgenus Timpanoqa Needham A broad e n t i r e f r o n t a l s h e l f on head; each femur p r o l o n g e d a p i c a l l y i n t o a sharp a c u t e s p i n e ; g i l l s on abdominal segments 4 t o 7 o n l y , o f t e n a r u d i m e n t a r y g i l l on segment 1; g i l l s on 4 t h segment o p e r c u l a t e ; body f l a t and wide, the w i d t h of the 5 t h abdominal segment b e i n g 2/3 to 3/4 the l e n g t h of the e n t i r e abdomen. EPHEfOERELLA Key To A d u l t s 1. S p i n e - l i k e t o o t h a t apex of f o r e t r o c h a n t e r . . . h e c u b a hecuba Eaton No d i s t i n c t s p i n e on apex of f o r e t r o c h a n t e r 2. 2. 3 r d j o i n t o f f o r c e p s a t l e a s t t w i c e as l o n g as wide 3. -171-3rd j o i n t o f f o r c e p s s c a r c e l y l o n g e r t h a n w i d e , 8. 3. 2nd j o i n t o f f o r c e p s s t r o n g l y bowed, w i t h a deep c o n s t r i c t i o n near the m i d d l e . . . . d o d d s i Needham 2nd j o i n t of f o r c e p s not. s t r o n g l y bowed, and w i t h no 'deep c o n s t r i c t i o n near base 4. 4. UJing v e n a t i o n p a l e f l a v i l i n e a IYlcD UJing v e n a t i o n dark or y e l l o w , 5. 5. UJing v e n a t i o n y e l l o w , c r o s s v e i n s p a l e l o d i lYIayo UJing v e n a t i o n d a r k . , . 6. 6. S u b g e n i t a l \" p l a t e between bases o f f o r c e p s not produced and w i t h o n l y a s h a l l o w e m a r g i n a t i o n . . q r a n d i s inqens IYlcD S u b g e n i t a l p l a t e between bases of f o r c e p s produced and w i t h a broad U-shaped e m a r g i n a t i o n . . . 7. 7. T a i l s brown c o l o r g d e n s i s Dodds T a i l s b l a c k . s p i n i f e r a Needham 8. L a t e r a l a p i c a l margins of penes p r o j e c t i n g ,forward as d i s t i n c t p r o c e s s e s , u s u a l l y s e v e r a l t o many s p i n e s on t h e penes..,9. L a t e r a l a p i c a l m a r gins of the penes rounded, and w i t h no f o r w a r d p r o j e c t i n g p r o c e s s e s . S p i n e s , i f p r e s e n t , b a r k - l i k e and d o r s o - l a t e r a l i n p o s i t i o n 13. 9. L a t e r a l a p i c a l p r o c e s s e s of the penes s h o r t , b l u n t and d i r e c t e d i n w a r d s . The a p i c a l n o t c h between the penes r e l a t i v e l y s h a l l o w 10. L a t e r a l a p i c a l p r o c e s s e s of the penes r a t h e r l o n g and s l e n d e r , d i r e c t e d f o r w a r d or outward. The a p i c a l n o t c h between the penes deeper.... 11. -172-10. 2nd j o i n t o f f o r c e p s not d i s t i n c t l y s w o l l e n a p i c a l l y . . , t i n e r m i s Eaton 2nd j o i n t of f o r c e p s ' d i s t i n c t l y s w o l l e n a p i c a l l y . . . i n f requens IYlcD 11. Abdominal s t e r n a u n i f o r m l y dark brown w i t h p a l e l a t e r a l margins on segments 8 and 9....'. j a c o b i IYlcD Abdominal s t e r n a each w i t h a s h a l l o w dark brown' chevron o r w i t h 3 brown l o n g i t u d i n a l s t r i p e s . . . .. ..12. 12'. Abdominal s t e r n a each w i t h a s h a l l o w dark brown c h e v r o n ....... '.'...' . ' . . . . . . . . . . h y s t r i x T r a v e r Abdominal s t e r n a each w i t h t h r e e brown l o n g i t u d i n a l s t r i p e s . '. . .\". . . . . . he-terocaudata IYlcD 13. Thorax b l a c k i s h . V e n a t i o n p a l e grey-brown, c r o s s v e i n s d i s t i n c t . Abdominal segments of male t r a n s l u c e n t w h i t i s h on the a n t e r i o r margins .\u00E2\u0080\u00A2 . t i b i a l i s IYlcD Thorax c h o c o l a t e brown. L o n g i t u d i n a l v e i n s l i g h t brown, c r o s s -v e i n s and i n t e r c a l a r i e s p a l e . Abdominal t e r g i t e s brown... '..14. 14. Abdominal t e r g i t e s u n i f o r m l y brown sp. 1 Abdominal t e r g i t e s brown, e x c e p t the p o s t e r i o r margin of each t e r g i t e dark brown . t e r e s a T r a v e r Key To IMymphs 1. G i l l s on abdominal segments 4 to 7. .....2. G i l l s on ab d o m i n a l segments 3 t o 7 3. 2. G i l l on segment 4 o p e r c u l a t e . D o r s a l s p i n e s o b s o l e s c e n t . No , g i l l on segment 1 ..hecuba hecuba Eaton G i l l on segment 4 s e m i - o p e r c u l a t e . D o r s a l s p i n e s on segment .1-10,moderately l o n g on segments 1-8, s h o r t and b l u n t on -173-segment 9, b a r e l y d i s c e r n i b l e on segment 10. Rudimentary g i l l on segment 1 . l o d i ITlayo 3. D o r s a l abdominal s p i n e s w a n t i n g . 4. D o r s a l abdominal s p i n e s p r e s e n t 6. 4. Teeth o r s p i n e s p r e s e n t on a n t e r i o r margin of f o r e femur....... d o d d s i Needham No t e e t h o r s p i n e s on a n t e r i o r margin o f f o r e femur .5. 5. \u00E2\u0080\u00A2 E n t i r e l a t e r a l m argin o f pronotum p a l e . L a t e r a l e x t e n s i o n s o f abdominal segments marked w i t h a dark median t r a n s v e r s e band. P a l e submedian s p o t s p r e s e n t on p o s t e r i o r margins of abdominal t e r g i t e s . 8 t e e t h on c l a w s . P i g m e n t a t i o n on upper p l a t e o f g i l l on segment 3 heavy i n e r m i s Eaton No d i s t i n c t p a l e m a r k i n g s on pronotum. No dark band on l a t e r a l e x t e n s i o n s o f abdominal segments. No p a l e submedian s p o t s \u00E2\u0080\u00A2 on p o s t e r i o r margins of t e r g i t e s , 5 - 6 t e e t h on c l a w s . P i g m e n t a t i o n o f upper p l a t e o f g i l l on segment 3 none or s l i g h t , i n f r e q u e n s fflcD 6. T e e t h oc s p i n e s p r e s e n t on a n t e r i o r margin o f f o r e femur..-..7. Teeth or s p i n e s w a n t i n g on a n t e r i o r margin o f f o r e femur, 8. 7. \"Thumb\" at d i s t a l end of f o r e t i b i a l o n g and s h a r p . Femora s l e n d e r . D o r s a l s p i n e s on segments 1-9 ., E o l o r a d e n s i s Dodds \"Thumb\" a t d i s t a l end of f o r e t i b i a s h o r t and b l u n t . Femora s t o u t . D o r s a l abdominal s p i n e s on segment 2-9 f l a v i l i n e a PflcD 8. L a t e r a l c e r c i l / 4 t o 3/4 as l o n g as the median t e r m i n a l f i l a m e n t s , . \u00C2\u00BB9\u00C2\u00AB -174-L a t e r a l c e r c i s u b e q u a l to t e r m i n a l , f i l a m e n t s * ,10. 9. M a x i l l a r y p a l p weak. A w h o r l of s p i n e s a t each t a i l j o i n i n g . . . , , . h e t e r o c a u d a t a McD M a x i l l a r y p a l p n o r m a l l y d e v e l o p e d . T a i l s may have w h o r l s o f s p i n e s i n the' b a s a l h a l f , ' f r i n g e d w i t h l o n g h a i r s i n a p i c a l p o r t i o n . h y s t r i x T r a v e r 10. T h o r a c i c t u b e r c l e s p r e s e n t 11. No t h o r a c i c t u b e r c l e s . ......12. 11. Submedian s p i n e o f pronotum, i f p r e s e n t , l a r g e and b l u n t , i n groups of 3. S u b m a r g i n a l p r o n o t a l s p i n e s s h o r t and b l u n t . . . q r a n d i s i n q e n s McD Submedian s p i n e o f pronotum r a t h e r s l e n d e r , s h a r p - p o i n t e d , 2 i n each group. S u b m a r g i n a l p r o n o t a l s p i n e s s h a r p at t i p s , w e l l d e v e l o p e d . s p i n i f e r a Needham 12. D o r s a l s p i n e s on abdominal segments 2 to 9. 7 t e e t h on c l a w s . No v e n t r a l m a r k i n g s , t i b i a l i s McD D o r s a l s p i n e s on segments 4 to 7. 9-10 t e e t h on c l a w s . Abdominal s t e r n a l l i g h t brown w i t h p a i r e d s u b l a t e r a l dark brown s t r e a k s ' t e r e s a T r a v e r s Unknown: E. j a c o b i McD EPHEMERELLA C0L0RADENSIS DODDS E p h e m e r e l l a c o l o r a d e n s i s Dodds, A l l e n and Edmunds, 1962, M i s c . Pub. Ent . Soc. Amer. 3 (5) : 157 ( B i b l i o g r a p h y A d u l t : T h i s s p e c i e s i s a member o f the subgenus P r u n e l l a . A dark brown or b l a c k i s h m a y f l y of moderate s i z e ; t h o r a x dark brown; no d i s t i n c t s p i n e s on the a p i c e s o f the f o r e t r o c h a n t e r s ; wing v e n a t i o n dark -175-p u r p l i s h brown; abdominal t e r g i t e s u n i f o r m dark brown w i t h p a l e m a r g i n s ; p l e u r a l f o l d p a l e ; s t e r n i t e s dark brown; s u b g e n i t a l p l a t e between bases of f o r c e p s produced and w i t h a broad U-shaped emarg-i n a t i o n ; a p i c a l margin o f f o r c e p s base almost s t r a i g h t ; 2nd j o i n t o f f o r c e p s may be s t r o n g l y bowed, but w i t h o u t a deep c o n s t r i c t i o n , o r m o d e r a t e l y and r e g u l a r l y c u r v e d , but not s w o l l e n near apex and t h i n n e r i n the m i d d l e ; 3 r d j o i n t a t l e a s t t w i c e as l o n g as wide; penes w i t h a U-shaped a p i c a l median c l e f t ; l o b e s o f penes expanded a p i c a l l y ; t a i l s brown, d a r k e r a t base. Nymph: F r o n t a l Rorns and f r o n t a l s h e l f w a n t i n g ; mouthparts v i s i b l e a n t e r i o r l y , genae not produced i n t o f l a n g e s or p r o j e c t i o n s ; head roughened, o c c i p u t o n l y roughened or b e a r i n g low, b l u n t , i n c o n s p i c u o u s t u b e r c l e s ; no s p i n e s o r t u b e r c l e s on pronotum or metanotum, o n l y a v e r y s h o r t median p o s t e r i o r t u b e r c l e on mesonotum; a n t e r i o r margins of f o r e femora w i t h t e e t h o r s p i n e s ; none on m i d d l e or h i n d femora; l e g s s t o u t , but more s l e n d e r than i n E. f l a v i l i n e a ; femora f l a t t e n e d , the p o s t e r i o r margins w i t h many h a i r s and a few s h o r t s p i n e s ; \"thumb\" a t d i s t a l end of f o r e t i b i a l o n g , s h a r p , and r e l a t i v e l y s t r a i g h t ; g i l l s on abdominal segments 3-7; no e l y t r o i d g i l l s ; p i g m e n t a t i o n of the upper p o r t i o n o f g i l l on segment 3 i s heavy and i n a w e l l -d e f i n e d 2 o r 3-lobed a r e a ; lower p o r t i o n o f t h i s g i l l has a p p a r e n t l y 3 l a y e r s of secondary l o b e s which a re broad o v a l o r s p a t u l a t e ; g i l l on segment 7. i s about l / 5 the l e n g t h o f the g i l l on segment 3; g i l l on segment 3 o v e r l a p s the one f o l l o w i n g by l / 3 or l e s s of i t s l e n g t h ; p a i r e d d o r s a l s p i n e s on t e r g i t e s 1-9, l o n g e r on t e r g i t e s 6-8; d o r s a l s p i n e s on these t e r g i t e s f a i r l y w e l l d e v e l o p e d ; s p i n e s on t e r g i t e 9 l o n g and s h a r p ; i f o c c i p i t a l t u b e r c l e s p r e s e n t , s p i n e s on t e r g i t e 9 -176-more a c u t e ; g e n e r a l c o l o u r l i g h t brown, m o t t l e d w i t h p a l e r , e s p e c i a l l y on the l e g s ; s t e r n i t e s may have s p a r s e h a i r s , but never an a d h e s i v e d i s c ; t a i l s each w i t h two dark and two p a l e r bands. D i s t r i b u t i o n ; C o l o r a d o , Montana, Wyoming, Ut a h , B r i t i s h C olumbia No specimens of t h i s s p e c i e s were examined. EPHEMERELLA DODDSI NEEDHAM E p h e m e r e l l a d o d d s i Needham, A l l e n and Edmunds, 1962, M i s c . Pub. E n t . Soc. Amer. 3 (5) : 163 ( B i b l i o g r a p h y ) A d u l t ; T h i s s p e c i e s i s p l a c e d i n the subgenus P r u n e l l a ; head and t h o r a x dark r e d d i s h - b r o w n ; f o r e femora dark p u r p l i s h brown, r e s t o f l e g p a l e r ; m i d d l e and h i n d l e g s y e l l o w i s h , femora shaded w i t h brown w i t h no dark a p i c a l bands; the t h r e e b a s a l t a r s a l j o i n t s shaded w i t h p u r p l i s h b l a c k ; no d i s t i n c t s p i n e on apex of f o r e t r o c h a n t e r ; wings h y a l i n e ; v e n a t i o n dark b rown; abdominal t e r g i t e s each w i t h a broad median t r a n s v e r s e dark brown band, p a l e r on d o r s a l a r e a s ; a n t e r i o r and p o s t e r i o r margins w i d e l y p a l e ; p l e u r a l f o l d p a l e ; s t e r n i t e s dark; 2nd j o i n t of f o r c e p s s t r o n g l y bowed w i t h a deep c o n s t r i c t i o n near the m i d d l e ; 3 r d f o r c e p s j o i n t a t l e a s t t w i c e as l o n g as wide; l o b e s of penes c o n s t r i c t e d a p i c a l l y ; t a i l s dark brown b a s a l l y , becoming p a l e a p i c a l l y . Nymph: A y e l l o w i s h t o t a n s p e c i e s ; d a r k e r on eyes , g i l l s , wing pads and bases o f t a i l s and t a r s i ; no f r o n t a l h o r n s ; a broad f r o n t a l s h e l f , notched to r e c e i v e the bases o f the antennae; o c c i p i t a l t u b e r c l e s w a n t i n g ; no t h o r a c i c s p i n e s or t u b e r c l e s ; t e e t h o r s p i n e s p r e s e n t on a n t e r i o r margins o f f o r e femora; s m a l l e r s p i n e s on p o s t e r i o r m a r g i n s . o f f o r e femora and both margins of o t h e r femora; a l l femora f l a t t e n e d ; t i b i a l \"thumb\" on f o r e l e g l / 3 as l o n g as t h e t a r s u s , s t r o n g , sharp a t t i p , and d i r e c t e d o u t w a r d l y ; no d o r s a l a b dominal s p i n e s ; abdominal t e r g i t e s shaded w i t h brou/n; g i l l s on abdominal segments 3-7; g i l l on segment 3 o v e r l a p s the one f o l l o w i n g by l / 3 i t s l e n g t h o r l e s s , but not e l y t r o i d ; upper p o r t i o n o f g i l l on segment 3 i s h e a v i l y pigmented i n a w e l l - d e f i n e d 2 o r 3-lobed a r e a ; s e c o n d a r y l o b e s o f l o w e r p o r t i o n o f g i l l on segment 3 w i t h 2 l a y e r s , broad o v a l o r s p a t u l a t e ; g i l l on segment 7 about l / 5 the l e n g t h o f the g i l l on segment 3; v e n t e r of the abdomen b e a r i n g an a d h e s i v e d i s c of l o n g h a i r s on i t s o u t e r margin and s h o r t h a i r s i n i n n e r space, e x t e n d i n g from s t e r n i t e s 1 t o 9; t a i l s y e l l o w i s h , d a r k e r b a s a i l y , l i g h t brown a p i c a l l y , s h o r t . E c o l o g y : Nymphs of t h i s s p e c i e s were taken from the m i d d l e o f f o u r l o c a t i o n s on the A l o u e t t e R i v e r , a t depths of 1 to 3 f e e t . The s u b s t r a t e c o n s i s t e d o f sand, g r a v e l , r o c k s , b o u l d e r s , and bed r o c k . The c u r r e n t , e x c e p t i n one case o f q u i e t r i p p l e s , was r a p i d . They were c o l l e c t e d the year round. D i s t r i b u t i o n ; Utah, Washington,.Montana, C o l o r a d o , C a l i f o r n i a , New M e x i c o , Wyoming, B r i t i s h C olumbia. M a t e r i a l Examined; 2 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Hane y), VI.2.59 (N.3. F i l m e r ) , 26 Nymphs, B r i t i s h C o l u m b i a : Loon Creek ( C l i n t o n ) , VI.16.56 (H. L o r z ) , 19 Nymphs, B r i t i s h C o l u m b i a : Loon Cr. ( C l i n t o n ) VI.13.? (H. L o r z ) . -178-EPHEIY1ERELLA FLAUILINEA IflcDUNNOUGH E p h e m e r e l l a f l a v i l i n e a McPunnough, A l l e n and Edmunds, 1962, M i s c . Pub. E n t . Soc. Amer., 3 (5) : 159 ( B i b l i o g r a p h y ) A d u l t : T h i s s p e c i e s b e l o n g s t o the subgenus P r u n e l l a ; a s m a l l m a y f l y ; head and t h o r a x deep ruddy brown; f o r e femora and t i b i a e deep b l a c k i s h brown, t a r s i w h i t i s h ; m i d d l e and h i n d l e g s d u l l y e l l o w i s h , a r e d d i s h brown a p i c a l p a t c h on i n n e r s u r f a c e of each femur; no b l a c k d o t s on femora; no d i s t i n c t s p i n e on apex o f f o r e t r o c h a n t e r ; wings h y a l i n e ; v e n a t i o n p a l e ; abdominal t e r g i t e s deep ruddy brown; p l e u r a l f o l d marked by a y e l l o w i s h l i n e e x t e n d i n g upwards i n each segment, e s p e c i a l l y i n the a p i c a l segments; s t e r n i t e s more r e d d i s h ; s u b g e n i t a l p l a t e between f o r c e p s bases not produced and w i t h o n l y a s h a l l o w e m a r g i n a t i o n ; 2nd f o r c e p s j o i n t ' s l i g h t l y bowed, or may be s t r o n g l y bowed, w i t h a deep c o n s t r i c t i o n near the apex; t i p of f o r c e p s bent i n w a r d ; 3 r d j o i n t o f f o r c e p s a t l e a s t t w i c e as l o n g as wide; a p i c a l l a t e r a l margins and l o b e s of penes expanded a p i c a l l y ; t a i l s b l a c k b a s a l l y , p a l e r a p i c a l l y . Nymph: A l i g h t t o dark brown nymph, i f l i g h t t h e y are d i s t i n c t l y m o t t l e d ; f r o n t a l horns w a n t i n g ; no f r o n t a l s h e l f , t h e mouthparts v i s i b l e a n t e r i -o r l y , and the genae not produced i n t o f l a n g e s or p r o j e c t i o n s ; p a i r e d o c c i p i t a l t u b e r c l e s u s u a l l y s h o r t and b l u n t , but may be m o d e r a t e l y l o n g and s h a r p ; no t h o r a c i c s p i n e s or. t u b e r c l e s ; l e g s s t o u t e r , f o r e t i b i a e s l e n d e r ; a n t e r i o r margin of f o r e femora w i t h t e e t h or s p i n e s ; o t h e r femora l a c k i n g such s p i n e s or t u b e r c l e s ; t i b i a l \"thumbs\" a t apex of f o r e t i b i a e s h o r t and b l u n t : femora w i t h t h r e e p a l e i n d i s t i n c t a r e a s ; t i b i a e w i t h d i s t i n c t p a l e bands a t each end; t a r s i banded i n -179-the m i d d l e ; d o r s a l a bdominal s p i n e s on segments 2-9, v e r y s m a l l on t e r g i t e 9; i f o c c i p i t a l t u b e r c l e s l o n g and s h a r p , abdominal s p i n e s on segment 9 m o d e r a t e l y l o n g ; a n d s h a r p : abdominal s p i n e s s h o r t ; g i l l s on a bdominal segments 3-7; g i l l on segment 3 o v e r l a p s the f o l l o w i n g one l / 3 i t s l e n g t h or l e s s , not e l y t r o i d ; p i g m e n t a t i o n of upper p o r t i o n of g i l l on-segment 3 i s heavy and i s of 1 l o b e ; secondary l o b e s of lower p o r t i o n of g i l l on segment 3 are e l l i p t i c a l t o s p a t u l a t e w i t h no b a s a l t h u m b - l i k e l o b e ; g i l l on segment 7 i s l / 5 the l e n g t h of t h a t on segment 3; t a i l s p a l e : w i t h narrow b l a c k i s h bands beyond the m i d d l e and a t the t i p s . E c o l o g y ; Nymphs of t h i s s p e c i e s were t a k e n from the m i d d l e and edges of many l o c a t i o n s on the A l o u e t t e R i v e r , ' a l w a y s a t a depth of 1 t o 2 f e e t . ' The stream bed v a r i e d from s i l t , t h r o u g h mud, sand, g r a v e l , r o c k s , b o u l d e r s , to bedrock; the c u r r e n t v a r i e d from q u i e t water to r a p i d s and f a l l s . They were c o l l e c t e d d u r i n g the e n t i r e y e a r . D i s t r i b u t i o n : Montana, Wyoming, A l b e r t a , B r i t i s h C o l u mbia. M a t e r i a l Examined: 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), VI.19.59 (N.3. F i l m e r ) , 2 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney) . V.26.59 (N.G. F i l m e r , 12 Nymphs, B r i t i s h C o l u m b i a : nr H e l l ' s Gate, VI.19.59 (G.G.E. Scudder) EPHEMERELLA GRANDIS INGEN5 McDUNNOUGH E p h e m e r e l l a q r a n d i s inqens McDunnough, A l l e n and Edmunds, 1962, M i s c . Pub. E n t . Soc. Amer. A d u l t : ' 3 (5) : 175 ( B i b l i o g r a p h y ) A b l a c k i s h m a y f l y b e l o n g i n g t o the subgenus P r u n e l l a ; head and t h o r a x b l a c k , l a t e r a l and p o s t e r i o r margins of mesonotum shaded s l i g h t l y w i t h brown, and a s l i g h t y e l l o w s h a d i n g on the median a r e a of the -180-metanotum; f o r e l e g s b l a c k i s h , w i t h the margins o f the femora near \u00E2\u0080\u00A2.bases t i n g e d w i t h a p a l e smoky y e l l o w ; femora o f m i d d l e and h i n d l e g s b l a c k i s h t i n g e d w i t h y e l l o w i s h a t bases and on m a r g i n s , r e s t y e l l o w i s h ; no d i s t i n c t s p i n e on apex o f f o r e t r o c h a n t e r ; wings h y a l i n e , the f o r e w i n g s u f f u s e d w i t h l i g h t amber i n b a s a l p o r t i o n ; v e n a t i o n b l a c k brown; s t i g m a t i c c r o s s v e i n s i n d i s t i n c t ; p o s t e r i o r f o r k of ffl n ot f u s e d w i t h C u l ; abdominal t e r g i t e s smoky y e l l o w or y e l l o w - b r o w n , each of t e r g i t e s 2-7 w i t h a l a r g e median q u a d r a t e b l a c k or deep p u r p l i s h brown p a t c h and l a t e r a l c i r c u l a r p a t c h e s of the same c o l o u r ; i n . a p i c a l segments the dark p a t c h e s more or l e s s c o a l e s c e ; s t e r n i t e s w i t h broad l i g h t y e l l o w - b r o w n p o s t e r i o r m a r g i n s , remainder b l a c k i s h w i t h a r e d d i s h t i n g e and f a i n t t r a c e s of s m a l l o b l i q u e submedian p a l e s t r e a k s on the a n t e r i o r m a r g i n s ; s u b g e n i t a l p l a t e between the f o r c e p s bases not produced and w i t h o n l y a s h a l l o w e r n a r g i n a t i o n ; 2nd f o r c e p s j o i n t not bowed and c o n s t r i c t e d , but i s i r r e g u l a r l y s w o l l e n ; 3 r d f o r c e p s j o i n t at l e a s t t w i c e as l o n g as wide; a p i c a l l a t e r a l margins of penes not expanded, the s i d e s n e a r l y bowed; l o b e s of penes expanded a p i c a l l y ; t a i l s b l a c k . Nymph; No f r o n t a l horns or f r o n t a l s h e l f ; o c c i p i t a l t u b e r c l e s l o n g ; submedian s p i n e s of pronotum i n groups of 3, l a r g e and b l u n t , p o s t e r i o r s p i n e o f each group s h o r t ; s u b m a r g i n a l s p i n e s o f pronotum s h o r t and b l u n t ; mesothorax w i t h 1 or 2 submedian p a i r s of t u b e r c l e s which are w e l l d e v e l o p e d and b l u n t to sharp,- and a s i n g l e m e d i a n . p o s t e r i o r t u b e r c l e ; submedian m e s o t h o r a c i c t u b e r c l e s may be j u s t a p a i r of submedian r i d g e s ; no t e e t h or s p i n e s on a n t e r i o r margins of f o r e femora; margins o f f o r e femora w i t h o n l y s c a t t e r e d h a i r s , not a r r a n g e d i n a m a r g i n a l row; l a t e r a l margins of a b d o m i n a l t e r g i t e s d i s t i n c t l y -181-convex; abdominal d o r s a l s p i n e s i n a r e g u l a r s e r i e s , f a i r l y c l o s e t o g e t h e r , t h o s e on segments 8 and 9 l a r g e r than the o t h e r s ; g i l l s on segments 3-7. D i s t r i b u t i o n : B r i t i s h C olumbia M a t e r i a l Examined: 1 Nymph, B r i t i s h C o l u m b i a : Loon Creek ( C l i n t o n ) , VI.16.56 (H. L o r z ) 2 Nymphs, B r i t i s h C o l u m b i a : Loon Creek ( C l i n t o n ) , VI.13.? (H. L o r z ) EPHEMERELLA HECUBA HECUBA EATON E p h e m e r e l l a hecuba hecuba E a t o n , Edmunds and A l l e n , 1959, Can. E n t . 91:54 ( B i b l i o g r a p h y ) A d u l t : T h i s s p e c i e s b e l o n g s t o the subgenus Timpanoqa; head m o t t l e d brown w i t h w h i t i s h m a r g i n s ; pronotum m o t t l e d brown, c a r i n a e r e d d i s h ; a n t e r i o r median p o r t i o n o f mesonotum brown, p o s t e r i o r p o r t i o n r e d d i s h brown; metanotum l i g h t y e l l o w ; f o r e t r o c h a n t e r w i t h a s p i n e - l i k e t o o t h a t i t s apex; f o r e femora dark brown w i t h b l a c k i s h m a r g i n s ; f o r e t i b i a e c u r v e d , n o t c h e d b a s a i l y on the a n t e r i o r m a r g i n s ; wings s e m i - h y a l i n e ; v e n a t i o n d i s t i n c t ; abdominal t e r g i t e s 1-4 dark y e l l o w , each w i t h a t r a n s v e r s e r e d d i s h s t r i p e which widens l a t e r a l l y and p o s t e r i o r l y i n t o a comma-shaped mark; on e i t h e r s i d e o f the median l i n e i s a' l i g h t y e l l o w c i r c u l a r ' s p o t which, e n l a r g e s p o s t e r i o r l y ; t e r g i t e s 5-10 a r e almost e n t i r e l y c o v e r e d by the r e d d i s h bands p o s t e r i o r l y and the w h i t i s h c i r c u l a r s p o t s a n t e r i o r l y ; p e r s i s t e n t r e s p i r a t o r y g i l l s a r e borne on segments 4 to 8; t e r g i t e s 9 and 10 bear prominent p o s t e r o - l a t e r a l s p i n e s ; each s t e r n i t e i s marked by a s e m i l u n a r y e l l o w i s h p o s t e r i o r margin and r e d d i s h a n t e r i o r and l a t e r a l m a r g i n s ; f o r c e p s l i g h t y e l l o w ; 2nd j o i n t o f f o r c e p s c o n s t r i c t e d near,, the apex; 3 r d f o r c e p s j o i n t s h o r t and em a r g i n a t e p o s t e r i o r l y ; -182C-a p i c a l p o r t i o n s of the penes a r e s e p a r a t e d by an i r r e g u l a r l y U-shaped n o t c h . Nymph; Body much f l a t t e n e d and h a i r y ; head c o m p a r a t i v e l y s m a l l ; head w i t h a broad e n t i r e f r o n t a l s h e l f ; no f r o n t a l h o r n s ; pronotum w i d e s t a t p o s t e r i o r m a r g i n , a s h o r t t u b e r c l e near m i d d l e o f each l a t e r a l m argin and a p a i r of s h o r t s u b m e d i a l t u b e r c l e s near p o s t e r i o r m a r g i n ; l e g s h a i r y ; m i d d l e coxae each b e a r s a s h o r t c o n i c a l s p i n e o r t u b e r c l e on i t s d o r s a l s u r f a c e ; each femur w i t h an a c u t e s p i n e at t h e apex, and the t r a c e s o f two b l a c k i s h bands; a b l a c k i s h band near the m i d d l e of each t i b i a ; b a s a l h a l f o f each t a r s u s b l a c k i s h ; abdomen s t o u t , f l a t t e n e d , w i d e s t a t 5 t h segment; t e r g i t e s 2-9 extended l a t e r a l l y i n t o ( sharp s a w - t o o t h - l i k e p o s t e r o - l a t e r a l s p i n e s which a r e p a l e b a s a l l y , c r o s s e d beyond the bases by wide b r o w n i s h bands, and r e d d i s h brown a t t i p s ; t e r g i t e s 4-6 w i t h o b s o l e s c e n t d o r s a l s p i n e s ; a dark brown median l i n e on t e r g i t e s 3 and 4; t e r g i t e s 5-9 w i t h f a i n t sub-median bro w n i s h a r e a s , and r e d d i s h l a t e r a l s t r e a k s n e x t to g i l l s ; a n t e r i o r h a l f and much of l a t e r a l p o r t i o n s of each s t e r n i t e marked w i t h wide r e d d i s h t o b r o w n i s h bands, and f a i n t i n d i c a t i o n s of p a l e submedian o b l i q u e marks a t a n t e r i o r m a r g i n ; g i l l s on segments 4-7; g i l l on segment 4 e l y t r o i d , c o v e r i n g the next one f o r 3/4 of i t s l e n g t h ; p i g m e n t a t i o n o f upper p o r t i o n of- g i l l on segment 4 i s l i g h t o r w a n t i n g ; t a i l s w i t h one or two narrow b l a c k i s h bands b a s a l l y , a wide b l a c k band a t 2/3 the d i s t a n c e from the base, and t i p s n a r r o w l y b l a c k . D i s t r i b u t i o n : C o l o r a d o , New M e x i c o , Utah, C a l i f o r n i a , B r i t i s h C olumbia. No specimens of t h i s s p e c i e s were examined. -183- ' EPHEITIERELLA HETEROCAUDATA McDUNNOUGH E p h e m e r e l l a h e t e r o c a u d a t a McDunnough, A l l e n and Edmunds, 1961, Ann, E n t . Sac. Amer. 54:603-12 ( B i b l i o g r a p h y ) A d u l t : T h i s s p e c i e s i s a member of the subgenus C a u d a t e l l a ; an o l i v e brown m a y f l y w i t h b l a c k m a r k i n g s ; t h o r a x d a r k . o l i v e brown, pronotum w i t h c o n s i d e r a b l e b l a c k s h a d i n g ; l e g s deep o l i v e , f o r e femora and t i b i a e t i n g e d w i t h b l a c k ; no s p i n e a t apex of f o r e t r o c h a n t e r ; no dark a p i c a l markings on m i d d l e and h i n d femora; wings h y a l i n e ; l o n g i t u d i n a l v e i n s smoky, c r o s s v e i n s p a l e ; abdominal t e r g i t e s o l i v e brown, w i t h a n t e r i o r broad b l a c k bands on t e r g i t e s 1-4, and s e m i c i r c u l a r a n t e r i o r p a t c h e s of the same c o l o u r on p o s t e r i o r t e r g i t e s ; t e r g i t e s a l s o w i t h l a t e r a l b l a c k p a t c h e s which tend t o f u s e w i t h the b l a c k bands on the a n t e r i o r t e r g i t e s ; s t e r n i t e s p a l e o l i v e w i t h t h r e e i r r e g u l a r l o n g i t u d i n a l b l a c k or brown s t r i p e s ; 3 r d f o r c e p s j o i n t s c a r c e l y l o n g e r than wide; penes u n i t e d , f o r m i n g an u p curved r o d , s w o l l e n a p i c a l l y ; l a t e r a l a p i c a l margins of penes rounded, w i t h no f o r w a r d p r o j e c t i n g p r o c e s s e s ; u s u a l l y b a r b - l i k e l a t e r a l d o r s a l s p i n e s p r e s e n t on penes, one on each s i d e ; t a i l s smoky, r i n g e d , the m i d d l e one t w i c e as l o n g as the o u t e r ones. Mymph: A dark brown nymph; head and t h o r a x smooth; labrum o n l y s l i g h t l y e m a r g i n a t e on a p i c a l m a r g i n ; m a x i l l a r y p a l p i weak, 3 - j o i n t e d ; no t h o r a c i c t u b e r c l e s ; l e g s s h o r t ; femora f l a t t e n e d ; no t e e t h or s p i n e s on a n t e r i o r margin of f o r e femora, a l t h o u g h t h e r e i s a d i s t i n c t row of m a r g i n a l h a i r s ; t i b i a e and t a r s i a l s o w i t h a d i s t i n c t row of h a i r s ; c l a w s w i t h a s i n g l e row of 7 d e n t i c l e s ; l e g s not banded; abdominal t e r g i t e s marked as i n imago; p a i r e d d o r s a l abdominal s p i n e s on segments -184-2-9, p r o m i n e n t , s t r o n g , i n c u r v e d ; abdominal d o r s a l s p i n e s becoming p r o g r e s s i v e l y l o n g e r and f u r t h e r a p a r t from t e r g i t e 2 t o 7, but s h o r t e r and c l o s e r t o g e t h e r on t e r g i t e s 8 and 9; no l a t e r a l e x t e n s i o n s on p o s t e r o - l a t e r a l s p i n e s or. t e r g i t e s ; p a t t e r n on s t e r n i t e s v a r i a b l e , may be a r e d d i s h brown median s t r i p e and a l i n e o f brown submedian dashes, or s t e r n i t e s may be u n i c o l o u r e d o r w i t h l i g h t l a t e r a l d o t s or s t r e a k s ; m i d d l e t a i l . 3 t i m e s as l o n g as the o u t e r ones, b r o w n i s h , j o i n i n g s d a r k e r and w i t h w h o r l s of s p i n e s ; g i l l s on segment 3-7. D i s t r i b u t i o n : Wyoming, B r i t i s h Columbia No specimens of t h i s s p e c i e s were examined. EPHEMERELLA HYSTRIX TRAVER E p h e m e r e l l a h y s t r i x T r a v e r , A l l e n and Edmunds, 1961, Ann. Ent. Soc. Arner. 54:603-12 ( B i b l i o g r a p h y ) . A d u l t : A member of the subgenus C a u d a t e l l a ; no d i s t i n c t s p i n e a t the apex o f the f o r e t r o c h a n t e r ; each abdominal s t e r n i t e marked w i t h a s h a l l o w dark brown c h e v r o n ; 3 r d f o r c e p s j o i n t s c a r c e l y l o n g e r than wide; penes u n i t e d , s w o l l e n a p i c a l l y ; l a t e r a l a p i c a l m a r gins of penes p r o j e c t i n g f o r w a r d as d i s t i n c t p r o c e s s e s ; l a t e r a l a p i c a l p r o c e s s e s of penes l o n g and s l e n d e r , d i r e c t e d f o r w a r d o r outward; deep a p i c a l n o t c h between penes; u s u a l l y s e v e r a l to many s p i n e s on penes. Nymph: A l i g h t r e d d i s h brown s p e c i e s ; head and t h o r a x smooth; no o c c i p i t a l t u b e r c l e s on f r o n t a l s h e l f ; labrum o n l y s l i g h t l y e m a r g i nate on a p i c a l m a r g i n ; m a x i l l a r y p a l p i n o r m a l l y d e v e l o p e d , 3 - j o i n t e d ; femora s l i g h t l y f l a t t e n e d ; no t e e t h o r s p i n e s on a n t e r i o r margins o f f o r e femora; s h o r t , i n c o n s p i c u o u s s p i n e s on p o s t e r i o r margins of femora; u s u a l l y no s p i n e s on the upper s u r f a c e s o f the f o r e femora, but i f p r e s e n t , -185-they a r e g e n e r a l l y d i s t r i b u t e d and not i n a t r a n s v e r s e a p i c a l band; t i b i a e and t a r s i w i t h o u t a d i s t i n c t row of h a i r s ; c l aws w i t h a s i n g l e row of 7-8 d e n t i c l e s ; l e g s unbanded, but j o i n i n g s o f l e g s , a p i c e s o f t a r s i , and claws dark r e d d i s h brown; p a i r e d d o r s a l a bdominal s p i n e s on segments 1-9 or 2-9, c u r v e d near t i p s , and each b e a r i n g a s e r i e s o f s p i n u l e s on a n t e r i o r margin near t i p ; s p i n e s on segment 2 s h o r t , c l o s e t o g e t h e r , and becoming p r o g r e s s i v e l y l o n g e r and f u r t h e r a p a r t p o s t e r i o r l y , l o n g e s t on segments 6 and 7, which a r e s u b e q u a l ; s p i n e s on segments 8 and 9 s h o r t e r , s l i g h t l y c o n v e r g e n t ; s p i n e s on m i d d l e segments c u r v e outward; abdominal t e r g i t e s w i t h s h o r t l a t e r a l e x t e n s i o n s b e a r i n g s h o r t p o s t e r o - l a t e r a l s p i n e s on segments 4-7, t h e s e b e i n g rounded and i n c u r v e d on segments 8 and 9; b a s a l t e r g i t e s p a l e r e d d i s h brown, becoming d a r k e r p o s t e r i o r l y , w i t h no p a l e d o r s a l s t r i p e , but t r a c e s of a dark median l i n e on segments 7 and 8, and dark submedian s t r e a k s on the p r e c e d i n g t e r g i t e s , and w i t h l a r g e dark l a t e r a l p a t c h e s on t e r g i t e s 8 and 9, and beneath g i l l s on o t h e r segments; abdominal s t e r n i t e s v a r i a b l e , may be u n i c o l o u r e d , or w i t h p a l e l a t e r a l d o t s o r s t r e a k s , or marked w i t h dark chevron-shaped m a r k i n g s , or each s t e r n i t e w i t h two broad l a t e r a l dark r e d d i s h brown t r i a n g l e s which a r e c o n n e c t e d on the a n t e r i o r m a r g i n ; g a n g l i o n i c a r e a s of s t e r n i t e s 1-6 p a l e , o f 7-8 dark brown; t a i l s unbanded; f r i n g e d w i t h l o n g h a i r s i n a p i c a l p o r t i o n , may have w h o r l s of s p i n e s a t j o i n i n g s i n b a s a l h a l f ; g i l l s on segments 3-7. E c o l o g y ; Nymphs of t h i s s p e c i e s have been ta k e n from the m i d d l e and edge of one l o c a t i o n on the A l o u e t t e R i v e r , at a depth o f 1-2 f e e t . The stream-bed c o n s i s t e d o f mud, g r a v e l , r o c k s , and b o u l d e r s . The c u r r e n t was r a p i d i n the m i d d l e , and q u i e t on the edge. They were c o l l e c t e d i n June. -186-D i s t r i b u t i a n ; Montana, B r i t i s h Columbia M a t e r i a l Examined: 2 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), VI.23.59 ( N . J . F i l m e r ) . ' EPHEMERELLA INERMIS EATON E p h e m e r e l l a i n a r m i s E a t o n , Needham, 1935, The B i o l o g y of M a y f l i e s , 604 ( B i b l i o g r a p h y ) A d u l t : A v e r y dark s p e c i e s ; . t h o r a c i c noturn p o l i s h e d deep b l a c k i s h brown; f o r e l e g d u l l g r e e n i s h g r e y ; femora l i g h t y e l l o w i s h amber i n a l l l e g s ; t a r s i d i r t y w h i t i s h ; wings h y a l i n e , a b l a c k i s h brown s p o t a t the extreme base of t h e f o r e w i n g ; v e n a t i o n p a l e , y e l l o w i s h t o h y a l i n e ; no s p i n e a t apex of f o r e t r o c h a n t e r ; abdominal t e r g i t e s dark r e d d i s h brown t o b l a c k i s h brown, the l a s t t h r e e y e l l o w i s h to r e d d i s h , l a t e r a l m argins l i g h t y e l l o w i s h , j o i n i n g s opaque; s t e r n i t e s p a l e r ; 2nd f o r c e p s j o i n t not s w o l l e n a p i c a l l y ; 3 r d f o r c e p s j o i n t s c a r c e l y l o n g e r t h a n wide; penes u n i t e d , somewhat s w o l l e n a p i c a l l y ; a p i c a l n o t c h between penes s h a l l o w ; l a t e r a l a p i c a l margins of.penes p r o j e c t i n g f o r w a r d as s h o r t , b l u n t , and i n w a r d l y d i r e c t e d p r o c e s s e s ; no a p i c a l s p i n e s on penes; but t h e r e a r e 4-5 l a t e r a l s p i n e s some d i s t a n c e from the apex on each s i d e ; t a i l s g r e y i s h w h i t e , j o i n i n g s opaque. Nymph: A dark r e d d i s h brown nymph; head and t h o r a x i r r e g u l a r l y m o t t l e d l i g h t and dark; l a t e r a l margins of pronotum p a l e ; l e g s b l a c k i s h brown, the femora, w i t h 3 l a r g e p a l e a r e a s , t i b i a e p a l e a t bases and a p i c e s , t a r s i p a l e a t a p i c e s ; l o n g s p i n e s a l o n g p o s t e r i o r m a rgins of the femora; and on the upper s u r f a c e s o f the f o r e femora a re l o n g s p i n e s a r r a n g e d i n an i r r e g u l a r t r a n s v e r s e a p i c a l band; no t e e t h or s p i n e s -187-\u00E2\u0080\u00A2 n the a n t e r i o r margins o f the f o r e femora; clau/s u/ith 8 t e e t h each; no d o r s a l abdominal s p i n e s ; w e l l d e v e l o p e d l a t e r a l e x t e n s i o n s o f abdominal t e r g i t e s p r e s e n t ; t e r g i t e s each w i t h a p a i r of s u b m e d i a l l a r g e p a l e s p o t s on p o s t e r i o r margin; on mi d d l e segments, e s p e c i a l l y 5 and 6, the median l i n e i s o f t e n p a l e and on t h e s e t e r g i t e s t h e r e a r e o f t e n l a r g e p a l e p a t c h e s j u s t above the g i l l s ; l a t e r a l e x t e n s i o n s marked by dark median t r a n s v e r s e bands; p o s t e r o - l a t e r a l s p i n e s on segments 6-8 s h o r t e r t h a n wide, on the o t h e r s , t h e w i d t h e q u a l s the l e n g t h ; s t e r n i t e s y e l l o w i s h - b r o w n , a p i c a l s t e r n i t e s and the l a t e r a l m argins of the m i d d l e ones b l a c k i s h brown; may be t r a c e s of dark submedian o b l i q u e dashes on the a n t e r i o r margins and of dark dots near the c e n t e r of the s t e r n i t e ; g i l l s on segments 3-7; no g i l l e l y t r o i d , the g i l l on segment 3 o v e r l a p s the f o l l o w i n g one l / 3 or l e s s of i t s l e n g t h ; . h e a v y p i g m e n t a t i o n on upper p o r t i o n o f g i l l on segment 3 i s i n 3 l o b e s , a l t h o u g h the s i d e l o b e s may be s m a l l ; lower p o r t i o n of g i l l on segment 3 i s c l e f t f o r l/2 i t s l e n g t h at most; g i l l on segment 7 i s minute; t a i l s y e l l o w i s h brown u s u a l l y w i t h many median and a p i c a l bands but may be unbanded, f r i n g e d w i t h l o n g h a i r s i n the a p i c a l p o r t i o n s , and never w i t h w h o r l s o f s p i n e s a t j o i n i n g s i n the b a s a l p o r t i o n s . E c o l o g y ; Nymphs of t h i s s p e c i e s have been c o l l e c t e d from the middle and edges of many l o c a t i o n s on the A l o u e t t e R i v e r , u s u a l l y from depth o f 1 to 2 f e e t , and o c c a s i o n a l l y deeper. The stream bed i n c l u d e d s i l t , mud, sand, g r a v e l , r o c k s , b o u l d e r s , and bedrock, and the c u r r e n t v a r i e d from q u i e t water t o r a p i d s . The nymphs were taken d u r i n g the e n t i r e y e a r . -188-D i s t r i b u t i o n : C o l o r a d o , Wyoming, Montana, Utah, Nevada, New M e x i c o , Oregon, B r i t i s h C o l u mbia. M a t e r i a l Examined: 3 Nymphs, B r i t i s h C o l u mbia: A l o u e t t e R i v e r (Haney), V.26.59 (N.3. F i l m e r ) , 4 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), XI.8.59, (N.3. F i l m e r ) , 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), IX.26.59 (N.3. F i l m e r ) . EPHEMERELLA INFREQUENS McDUNNOUGH E p h e m e r e l l a i n f r e q u e n s McDunnough, Needham, 1935, The B i o l o g y o f M a y f l i e s , 605 ( B i b l i o g r a p h y ) A d u l t : A r e d d i s h brown m a y f l y ; eyes o f male l i g h t orange; head l i g h t brown; pronotum and a n t e r i o r l a t e r a l m argins o f mesonotum p u r p l i s h brown; r e s t o f mesonotum deep o l i v e brown, r e d d i s h brown p o s t e r i o r l y w i t h 2 s l i g h t l y r a i s e d b l a c k i s h l i n e s a n t e r i o r to t h e s c u t e l l u m ; l e g s l i g h t y e l l o w ; wings h y a l i n e , bases t i n g e d w i t h y e l l o w i s h brown; v e n a t i o n p a l e ; c r o s s v e i n s i n d i s t i n c t , e s p e c i a l l y i n b a s a l c o s t a l space; no s p i n e s on apex o f f o r e t r o c h a n t e r ; abdominal t e r g i t e s l i g h t r e d d i s h brown, the p o s t e r i o r margins smoky; p l e u r a l f o l d n a r r o w l y y e l l o w i s h ; s t e r n i t e s d u l l p u r p l i s h brown, a p i c a l s t e r n i t e s y e l l o w i s h brown, and middle s t e r n i t e s w i t h t r a c e s o f p a l e semi t r a n s p a r e n t a r e a s on a n t e r i o r m a r g i n s ; 2nd f o r c e p s j o i n t d i s t i n c t l y s w o l l e n a p i c a l l y ; 3 r d f o r c e p s j o i n t s c a r c e l y l o n g e r than wide; penes u n i t e d , somewhat s w o l l e n a p i c a l l y ; a p i c a l n o t c h between penes s h a l l o w ; l a t e r a l a p i c a l m a r gins of penes p r o j e c t i n g f o r w a r d as d i s t i n c t s h o r t , b l u n t , i n w a r d l y d i r e c t e d p r o c e s s e s ; penes each w i t h 2-4 a p i c a l s p i n e s , and 4-5 o t h e r s , i n 2 gr o u p s , f u r t h e r down; t a i l s y e l l o w i s h b a s a l l y , w h i t i s h a p i c a l l y , w i t h j o i n i n g s n a r r o w l y r i n g e d w i t h dark brown. -189-Nymph: A dark r e d d i s h t o b l a c k i s h brown s p e c i e s ; v e r t e x , l a t e r a l p o r t i o n s of pronotum, and a n t e r i o r p o r t i o n of mesonotum i n d i s t i n c t l y m o t t l e d w i t h dark brown: no d i s t i n c t p a l e markings on pronotum; l e g s r e d d i s h brown, femcra i r r e g u l a r l y b l o t c h e d w i t h y e l l o w i s h , t i b i a e and t a r s i p a l e banded b a s a i l y and a p i c a l l y ; no t e e t h or s p i n e s on a n t e r i o r margins o f f o r e femora; l o n g s p i n e s on p o s t e r i o r margins of a l l femora, and a l s o on upper s u r f a c e i n a t r a n s v e r s e a p i c a l band; claws w i t h 5-6 d e n t i c l e s ; no d o r s a l abdominal s p i n e s ; l a t e r a l e x t e n s i o n s of t e r g i t e s l e s s d e v e l o p e d than i n E. i n e r m i s ; no dark t r a n s v e r s e band on t h e s e l a t e r a l e x t e n s i o n s ; abdominal t e r g i t e s u s u a l l y w i t h a p a l e m i d - d o r s a l l i n e ; no p a l e s p o t s on p o s t e r i o r margins of t e r g i t e s or p a l e l a t e r a l a r e a s above g i l l s ; s t e r n i t e s unmarked; g i l l s on segments 3-7; no e l y t r o i d g i l l s ; g i l l on segment 3 o v e r l a p s the f o l l o w i n g one l / 3 or l e s s of i t s l e n g t h ; p i g m e n t a t i o n on upper p o r t i o n of g i l l on segment 3 i s none or s l i g h t ; upper p o r t i o n of g i l l on segment 3 w i t h a l o b e d base, t h i s p o r t i o n i s l o n g e r than the l o w e r p o r t i o n by l / 4 ; g i l l on segment 7 i s l e s s than l / 3 the l e n g t h of the g i l l on segment 3; t a i l s r e d d i s h brown, w i t h s e v e r a l y e l l o w i s h bands, f r i n g e d w i t h l o n g h a i r s i n a p i c a l p o r t i o n ; and never w i t h w h o r l s o f s p i n e s a t the j o i n i n g s of the b a s a l p o r t i o n . D i s t r i b u t i o n : C a l i f o r n i a , Utah, Montana, Wyoming, A l b e r t a , B r i t i s h C o l u m bia. No specimens o f t h i s s p e c i e s were examined. EPHEMERELLA 3AC0BI McDUNNOUGH E p h e m e r e l l a j a c o b i McDunnough, A l l e n and t-dmunds, 1961, Ann. Ent. Soc. Amer. 54:603-612 ( B i b l i o g r a p h y ) -190-A d u l t : T h i s s p e c i e s i s a member o f the subgenus C a u d a t e l l a ; t h o r a x deep brown; eyes b l a c k i s h w i t h a r e d d i s h t i n g e ; no s p i n e on apex of f o r e t r o c h a n t e r ; wings narrow, h y a l i n e ; l o n g i t u d i n a l v e i n s i n c o s t a l h a l f p a l e b r o w n i s h ; c r o s s v e i n s p a l e and i n c o n s p i c u o u s ; abdominal t e r g i t e s b l a c k i s h , p o s t e r i o r margins b r o w n i s h , p r o d u c i n g a r i n g e d appearance; s t e r n i t e s u n i f o r m l y dark brown; l a t e r a l margins of s t e r n i t e s 8 and 9 p a l e ; penes s h o r t and br o a d ; a p i c a l n o t c h between penes deep; l a t e r a l a p i c a l margins of penes p r o j e c t f o r w a r d as s h o r t , b l u n t , i n w a r d l y d i r e c t e d p r o c e s s e s ; u s u a l l y s p i n e s on penes; 3 r d f o r c e p s j o i n t s c a r c e l y l o n g e r than wide; t a i l s o f f e m a l e b l a c k i s h a t base, p a l i n g a p i c a l l y , and d i s t i n c t l y dark r i n g e d . Nymph: Unknown D i s t r i b u t i o n : B r i t i s h C olumbia No specimens of t h i s s p e c i e s were examined. EPHEMERELLA LODI MAYO Ep h e m e r e l l a l o d i Mayo, A l l e n and Edmunds, 1963, Can. Ent. 95:621 ( B i b l i o g r a p h y ) A d u l t : (Male) T h i s s p e c i e s has been p l a c e d i n the subgenus E u r y l o p h e l l a ; pronotum y e l l o w i s h brown t i n g e d w i t h r e d ; r e s t of t h o r a x r e d d i s h brown; wings s l i g h t l y a m b e r - t i n g e d ; v e n a t i o n y e l l o w , c r o s s v e i n s p a l e ; s t i g m a t i c c r o s s v e i n s anastomosed; wings o f female w i t h r e d d i s h c o l o u r i n g a t the bases of the 5c and R; abdomen l i g h t e r t h a n \" t h e t h o r a x ; t e r g i t e s 1-3 are r e d d i s h brown, w i t h wide brown bands on the p o s t e r i o r m a r g i n s ; t e r g i t e s 4-10 y e l l o w i s h w i t h r e d d i s h brown p o s t e r i o r m a r g i n s ; t e r g i t e s 8 and 9 w i t h a r e d d i s h s t r e a k near the p l e u r a l f o l d ; l a t e r a l l y each -191-t e r g i t e i s marked w i t h a b l a c k o b l i q u e s t r e a k near the p l e u r a l f o l d , and w i t h b l a c k i s h s p o t s or s t r e a k s on each s i d e of the m i d l i n e ; the female i s l i g h t e r , the d o r s a l m arkings b e i n g a m o t t l e d r e d , and a wide m o t t l e d m i d d o r s a l s t r e a k ; t a i l s y e l l o w , the j o i n i n g s a dark r e d d i s h brown; 2nd f o r c e p s j o i n t not s t r o n g l y bowed o r c o n s t r i c t e d ; 3 r d f o r c e p s j o i n t a t l e a s t t w i c e as l o n g as wide. Nymph: A dark brown nymph, o f t e n w i t h a p a l e median s t r i p e on the head, t h o r a x , and abdomen, and w i t h s c a t t e r e d p a l e s p o t s and maculae; female w i t h p a i r e d o c c i p i t a l t u b e r c l e s , male w i t h o u t ; c l a w s w i t h 7-10 d e n t i c l e s ; d o r s a l abdominal s p i n e s on t e r g i t e s 1-10, d e c r e a s i n g i n s i z e p o s t e r i o r l y ; m o d e r a t e l y l o n g on t e r g i t e s 1-8, s h o r t and b l u n t on 9, b a r e l y d i s c e r n a b l e on 10, w i d e s t a p a r t on segments 2-4; p o s t e r o -l a t e r a l s p i n e s w e l l d e v e l o p e d on segments 2 and 3; t e r g i t e s r i c h brown w i t h 3-4 p a l e d o t s between t u b e r c l e s ; t e r g i t e s 2-4 o f t e n w i t h wide p a l e s u b l a t e r a l s t r i p e s and 9-10 w i t h narrow p a l e submedian s t r i p e s ; t a i l s a l t e r n a t e l y banded w i t h narrow l i g h t brown and wide dark brown bands; g i l l s on segments 4-7; r u d i m e n t a r y g i l l on segment 1; g i l l on segment 4 s e m i - o p e r c u l a t e . E c o l o g y ; T h i s s p e c i e s has been taken from the edges of two l o c a t i o n s on the A l o u e t t e R i v e r , a t depths of 1 to 2 f e e t . The s t r e a m bed c o n s i s t e d of s i l t , mud, and r o c k s . The c u r r e n t was s t i l l and q u i e t . They were tak e n i n 3une. In one c a s e , however, one nymph was t a k e n i n November from the m i d d l e o f t h e r i v e r , from a s u b s t r a t e of r o c k s , g r a v e l , and b o u l d e r s , i n a r i p p l i n g c u r r e n t . D i s t r i b u t i o n : B r i t i s h C olumbia. -192-M a t e r i a l Examined; 2 Nymphs,. B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), VI.9.59 ( N . J . F i l m e r ) EPHEIY1ERELLA SPINIFERA NEEDHAM Ep h e m e r e l l a s p i n i f e r a Needham, A l l e n and Edmunds, 1963, M i s c . Pub. E n t . Soc. Amer. 3 (5) : 176 ( B i b l i o g r a p h y ) A d u l t : T h i s s p e c i e s i s a member of the subgenus P r u n e l l a ; no s p i n e a t apex of f o r e t r o c h a n t e r ; wings h y a l i n e ; v e n a t i o n dark brown; abdominal t e r g i t e s 2-6 b l a c k o r deep p u r p l i s h brown w i t h p a l e r m a r g i n s ; s t e r n i t e s w i t h dark m a r k i n g s ; 2nd f o r c e p s j o i n t not bowed or c o n s t r i c t e d , c o n s i d -e r a b l y w i d e r a t base t h a n a t apex; 3 r d f o r c e p s j o i n t a t l e a s t t w i c e as l o n g as wide; s u b g e n i t a l p l a t e between the f o r c e p s bases produced and w i t h a broad V-shaped e m a r g i n a t i o n ; penes w i t h a U-shaped a p i c a l median c l e f t ; l o b e s of penes expanded a p i c a l l y ; t a i l s b l a c k . Nymph: No f r o n t a l horns or f r o n t a l s h e l f ; p rominent o c c i p i t a l t u b e r c l e s ; pronotum w i t h w e l l - d e v e l o p e d , s h a r p - p o i n t e d s u b m a r g i n a l s p i n e s , and 2 p a i r s of s l e n d e r , s h a r p p o i n t e d s u b m e d i a l s p i n e s , the i n t e r i o r s p i n e i n each p a i r b e i n g t w i c e as h i g h as the p o s t e r i o r one, mesonotum w i t h a p a i r of submedian t u b e r c l e s on the a n t e r i o r m a r g i n , two p a i r s of submedian s p i n e s , the p o s t e r i o r p a i r b e i n g the l a r g e r , and a median t u b e r c l e on the p o s t e r i o r m a r g i n ; prosternum w i t h a median t u b e r c l e ; no t e e t h o r s p i n e s on f o r e femora w i t h o n l y s c a t t e r e d h a i r s , not a r r a n g e d i n a m a r g i n a l row; t i b i a l \"thumb\" s l e n d e r , sharp p o i n t e d , not r e a c h i n g to m i d d l e of t a r s u s ; d o r s a l abdominal s p i n e s p r o m i n e n t , tho s e on segments 2-7 s u b e q u a l , t h o s e on 8 and 9 f o u r t i m e s as l o n g as the p r e c e d i n g ones; s p i n e s on segment 8 may be s t r o n g l y bent -193-backward o r downward; t e r g i t e s p a l e b r o w n i s h to r e d d i s h brown, s t e r n i t e s y e l l o w i s h , w i t h i n d i s t i n c t d a r k e r dashes on each s i d e ; g i l l s on abdominal segments 3-7; no g i l l e l y t r o i d , g i l l on segment 3 o v e r l a p s the f o l l o w i n g one by l / 3 or l e s s of i t s l e n g t h ; upper p o r t i o n of g i l l on segment 3 2/3 or more l o n g e r than the l o w e r p o r t i o n , p i g m e n t a t i o n i n t h i s p o r t i o n i s heavy and g e n e r a l , showing no l o b i n g ; l o w e r p o r t i o n of g i l l on segment 3 of o n l y 2 l a y e r s , t h e secondary l o b e s not c l o s e t o g e t h e r ; g i l l on segment 7 m i n u t e ; t a i l s y e l l o w i s h , banded, w h o r l s o f s p i n e s a t j o i n i n g s . E c o l o g y : Nymphs o f t h i s s p e c i e s were t a k e n from the m i d d l e of 3 l o c a t i o n s on the A l o u e t t e R i v e r , a t depths of 1 t o 5 f e e t . The st r e a m bed c o n s i s t e d o f sand, g r a v e l , r o c k s , and b o u l d e r s , and the c u r r e n t v a r i e d from q u i e t r i p p l e s t o r a p i d s . They were a l s o found from the edge o f one of t h e s e l o c a t i o n s , i n q u i e t w a t e r . They were c o l l e c t e d i n Dune and November. D i s t r i b u t i o n ; Montana, Utah, B r i t i s h C o l u mbia. M a t e r i a l Examined: 2 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney) VI.23.59 (N.3. F i l m e r ) EPHEMERELLA TERESA TRAVER E p h e m e r e l l a t e r e s a T r a v e r , A l l e n and Edmunds, 1963, Ann. E n t . Soc. Amer. 56 (5) : 583-600 A d u l t : T h i s s p e c i e s b e l o n g s to the subgenus S e r r a t e l l a ; head brown; t h o r a x c h o c o l a t e brown; l e g s l i g h t brown; wings h y a l i n e ; l o n g i t u d i n a l v e i n s l i g h t brown, o t h e r s p a l e ; no s p i n e on apex of f o r e t r o c h a n t e r ; abdominal t e r g i t e s brown, p o s t e r i o r margins d a r k e r ; s t e r n i t e s l i g h t brown; 3rd f o r c e p s j o i n t s c a r c e l y l o n g e r than wide; penes not c o n s t r i c t e d -194-near the base, the s i d e s n e a r l y p a r a l l e l , and the i n n e r margin of each p e n i s l o b e i s w i t h o u t a s u b a p i c a l n o t c h ; p e n i s l o b e s w i t h o u t l a t e r a l s u b a p i c a l p r o j e c t i o n s ; t a i l s p a l e , r i n g e d w i t h dark brown a t j o i n i n g s . Nymph: Head and t h o r a x smooth; m a x i l l a r y p a l p i v e r y s m a l l , a p p a r e n t l y w a n t i n g ; median l i n e o f pronotum e l e v a t e d a n t e r i o r l y , d e p r e s s e d p o s t e r i o r l y , w i t h c a r i n a e on l a t e r a l s m a r g i n ; no t e e t h on a n t e r i o r margins of f o r e femora, and no s p i n e s ; l e g s p a l e brown, a p i c e s of j o i n t s r e d d i s h brown; c l a w s w i t h 9-10 d e n t i c l e s ; wing pads w i t h a c o s t a l margin p u r p l i s h ; d o r s a l abdominal s p i n e s on segments 4-7 o n l y , s h o r t and f a r a p a r t on 4, l o n g e r and c l o s e r t o g e t h e r on the r e s t ; l a t e r a l e x t e n s i o n and p o s t e r o - l a t e r a l s p i n e s on abdominal t e r g i t e s m o d e r a t e l y d e v e l o p e d ; t e r g i t e s p a l e r e d d i s h brown w i t h d a r k e r l a t e r a l p a t c h e s on t e r g i t e s 4-8 and dark d o t s on t e r g i t e 9; s t e r n i t e s y e l l o w i s h w i t h a row o f dark l a t e r a l dashes; g a n g l i o n i c a r e a s o f t e n darkened; g i l l s on segments 3-7; t a i l s p a l e y e l l o w i s h , each j o i n i n g w i t h a w h o r l o f dark r e d d i s h brown s p i n e s , may be dark i n d i s t a l h a l f . E c o l o g y : These nymphs were c o l l e c t e d from the m i d d l e o f s e v e r a l l o c a t i o n s of the A l o u e t t e R i v e r , from a depth o f 1 to 2 f e e t . The s u b s t r a t e c o n s i s t e d of g r a v e l , r o c k s , b o u l d e r s , and bedrock. In a l l c a s e s the c u r r e n t was r a p i d . A l l specimens were ta k e n d u r i n g 3une and Du l y . D i s t r i b u t i o n : C a l i f o r n i a , B r i t i s h Columbia M a t e r i a l Examined: 1 Nymph, B r i t i s h C olumbia: A l o u e t t e R i v e r (Haney), VI.2.59 (N.3. F i l m e r ) , 2 Nymphs, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), VI.23.59 (N.3. F i l m e r ) . -195-EPHEfflERELLA TIBIALIS fflcDUNNOUGH E p h e m e r e l l a t i b i a l i s fflcDunnough, A l l e n and Edmunds, 1963, Ann. E n t . Soc. Amer. 56 (5) : 583-600 A d u l t ? T h i s s p e c i e s has been p l a c e d i n the subgenus S e r r a t e l l a ; males deep p u r p l i s h brown; t h o r a x b l a c k i s h d o r s a l l y ; l e g s y e l l o w i s h ; f o r e t i b i a e deep smoky, m i d d l e and h i n d t i b i a e w i t h r e d d i s h a p i c a l bands; f o r e t i b i a e t w i c e as l o n g as the femora; no s p i n e s at apex of f o r e t r o c h a n t e r ; wings v i t r e o u s ; v e n a t i o n p a l e grey-brown; c r o s s v e i n s d i s t i n c t ; abdominal t e r g i t e s 3-8 w i t h narrow w h i t i s h t r a n s l u c e n t a n t e r i o r m a r g i n s ; s t e r n i t e s w i t h s l i g h t l y darkened g a n g l i o n i c a r e a s ; 3 r d f o r c e p s j o i n t s c a r c e l y l o n g e r than wide; penes b l a c k i s h ; u n i t e d , s w o l l e n a p i c a l l y ; penes c o n s t r i c t e d near base, i n n e r margin of each l o b e w i t h a s u b a p i c a l n o t c h ; p e n i s l o b e s rounded on l a t e r a l a p i c a l m a r g i n s , w i t h o u t a s u b a p i c a l p r o j e c t i o n ; u s u a l l y w i t h b a r b - l i k e d o r s o - l a t e r a l s p i n e s , one on each s i d e of each p e n i s ; middle t a i l n o t n o t i c e a b l y l o n g e r t h a n the o u t e r ones; t a i l s smoky, d a r k e r a t j o i n i n g s . Nymph; Head and t h o r a x smooth, w i t h o u t h a i r s or t u b e r c l e s ; m a x i l l a r y p a l p i m o d e r a t e l y l o n g ; t h o r a x and abdomen s l e n d e r and b l a c k i s h , sometimes w i t h a narrow m i d - d o r s a l p a l e l i n e ; l e g s s h o r t ; no t e e t h o r s p i n e s o n a n t e r i o r margins of f o r e femora; no c o n s p i c u o u s h a i r s on l e g s ; l e g s p u r p l i s h brown, r e d , or f u s c i o u s w i t h a s m a l l p a l e spot b a s a l l y and a p a l e a p i c a l band and i n c o m p l e t e s u b a p i c a l mark on each femur; t i b i a e and t a r s i each w i t h b a s a l and a p i c a l p a l e bands; c l a w s w i t h 5-7 d e n t i c l e s ; d o r s a l abdominal s p i n e s on segments 2-9, narrow and a c u t e ; p o s t e r i o r margins of t e r g i t e s s t r a i g h t ; t u b e r c l e s may be -196-s w o l l e n on segments 2 and 8; l a t e r a l e x t e n s i o n s o f abdominal t e r g i t e s not prominent; p o s t e r o - l a t e r a l s p i n e on segment 9 not e x t e n d i n g beyond the margin o f segment 10; s t e r n i t e s unmarked; g i l l s on segments 3-7; t a i l s a p p r o x i m a t e l y equal i n l e n g t h , a l t e r n a t e l y banded brown and p a l e ; w h o r l s of s p i n e s a t each j o i n i n g . E c o l o g y : Nymphs of t h i s s p e c i e s mere t a k e n from many l o c a t i o n s on the A l o u e t t e R i v e r , u s u a l l y a t depths o f from 1 t o 2 f e e t . The stream bed v a r i e d from mud, t h r o u g h sand, g r a v e l and r o c k s , to b o u l d e r s . The c u r r e n t was u s u a l l y r i p p l i n g , but o c c a s i o n a l l y was q u i e t or r a p i d . They were c o l l e c t e d d u r i n g the whole y e a r , e x c e p t d u r i n g the w i n t e r months of October t o J a n u a r y . D i s t r i b u t i o n ; Wyoming, C a l i f o r n i a , B r i t i s h C o l u mbia. M a t e r i a l Examined; 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney), VI.16.59, ( N . J . F i l m e r ) ; 1 Nymph, B r i t i s h C o l u m b i a : A l o u e t t e R i v e r (Haney) V I I I . 2 6 . 5 9 ( N . J . F i l m e r ) . E p h e m e r e l l a sp. 1 A d u l t : T h i s a d u l t c l o s e l y resembles E . t e r e s a , the o n l y d i f f e r e n c e b e i n g the l a c k o f a dark margin on each abdominal t e r g i t e . F u r t h e r i n v e s t i g a t i o n may p l a c e t h i s specimen i n t h a t s p e c i e s . Nymph: Unknown D i s t r i b u t i o n : B r i t i s h Columbia M a t e r i a l Examined: 1 Male, B r i t i s h C o l u m b i a : Q u e s n e l , VI.31.48 (H.R. McCarthy) -197-SUBFAIYIILY LEPTOHYPHIIMAE Genus T r i c o r y t h o d e s Ulmer T r i c o r y t h o d e s , IMeedharn, 1935, The B i o l o g y of M a y f l i e s , 630 ( b i b l i o g r a p h y ) A d u l t : S m a l l t o moderate s i z e d m a y f l i e s , u s u a l l y b l a c k i s h or dark brown, fe m a l e s p a l e r ; eyes w i d e l y s e p a r a t e d ; f o r e l e g o f male s l e n d e r , almost o r as l o n g as the body;- f o r e femur 2/5 as l o n g as the t i b i a , which i s 1-1/2 t i m e s as l o n g as the t a r s u s ; t a r s i 5 - j o i n t e d , 2nd j o i n t may be as l o n g as femur; m i d d l e and h i n d femora l o n g e r than t i b i a e , and 2-1/2 t i m e s as l o n g as t a r s i ; t e r m i n a l t a r s a l j o i n t the l o n g e s t ; c l a w s of m a l e f o r e t a r s u s s i m i l a r , b l u n t , a l l o t h e r s d i s s i m i l a r ; p o s t e r i o r branch of IYI of f o r e w i n g and the l o n g i n t e r c a l a r y between the branches o f the IYI, s h o r t e r than the a n t e r i o r b r a n c h , not e x t e n d i n g t o the base; c r o s s v e i n s numerous; Sc and R u s u a l l y p u r p l i s h b l a c k e x c e p t a t apex; f o r c e p s 3 r j o i n t e d , 2nd j o i n t w i t h an o v o i d s w e l l i n g a t base of i n n e r m a r g i n , r e s t l o n g , s l e n d e r , and t a p e r i n g , 3 r d j o i n t s h o r t , o v o i d ; f o r c e p s base e n t i r e , a p i c a l margin d e e p l y e x c a v a t e d m e d i a l l y ; penes .united f o r 3/4 of t h e i r l e n g t h , f o r m i n g a c o n i c a l s t r u c t u r e ; d i s t a l p o r t i o n s s e p a r a t e d by a rounded or U-shaped n o t c h ; p o s t e r i o r m argin of s u b a n a l p l a t e of femal e e n t i r e o r s l i g h t l y o b t u s e ; t a i l s t h r e e . Mymph: A p i c a l margin of labrum d e e p l y notched m e d i a l l y ; i n n e r c a n i n e s of m a n d i b l e s as l o n g as o u t e r ones; m a x i l l a r y p a l p i r e d u c e d : l a b i a l p a l p i 3 - j o i n t e d , s m a l l ; c laws not p e c t i n a t e ; no g i l l rudiment on abd o m i n a l segment 1; g i l l s on segments 2-6 d o u b l e , a r g i n s of each -198-p l a t e e n t i r e , not f r i n g e d ; upper p l a t e o f g i l l on segment 2 l a r g e , e l y t r o i d , t r i a n g u l a r , lower p l a t e b i f i d , s m a l l e r , c o n s i s t i n g o f a l o n g s l e n d e r p o r t i o n and an o v o i d one; t a i l s t h r e e , w i t h a w h o r l o f s p i n e s a t each j o i n i n g . Genotype; T r i c o r y t h o d e s e x p l i c a t u s ( i n T r i c o r y t h u s ) Eaton TRICORYTHODES (YIINUTU5 TRAVER T r i c o r y t h o d e s minutus T r a v e r , Needham, 1935, The B i o l o g y of fflayfli.es, 636 ( B i b l i o g r a p h y ) A d u l t ; ) A s m a l l r e d d i s h brown m a y f l y ; head o f male b r i g h t r e d d i s h w i t h a b l a c k i s h p o s t e r i o r margin; t h o r a x red-brown, pronotum shaded w i t h b l a c k m e d i a l l y and l a t e r a l l y , mesonotum deeper i n c o l o u r ; l e g s l i g h t r e d d i s h - b r o w n , e x c e p t f o r e t i b i a e . a n d t a r s i which a re w h i t i s h , wings h y a l i n e , w h i t i s h ; v e n a t i o n , e x c e p t f o r the p u r p l i s h Sc and R, p a l e ; abdomen r e d d i s h brown; t e r g i t e s 1, 2, 8, and 9 l a r g e l y b l a c k i s h ; m i d d l e t e r g i t e s w i t h a red-brown median l i n e . o n each s i d e o f which i s heavy b l a c k i s h s h a d i n g , b e a r i n g a p a i r o f l a r g e b l a c k l a t e r a l t r i a n g l e s on s t e r n i t e 9; f o r c e p s base s h a l l o w l y e x c a v a t e d . Nymph; Unknown D i s t r i b u t i o n ; B r i t i s h C o l u m b i a , Utah ' No specimens o f t h i s s p e c i e s were examined. T r i c o r y t h o d e s sp. 1 A d u l t : Unknown Nymph: Abdominal t e r g i t e s w i t h b l a c k m arkings and a p a l e narrow median l i n e ; o p e r c u l a t e g i l l s b o r d e r e d w i t h b l a c k on the m e d i a l and p o s t e r i o r edges. -199-D i s t r i b u t i o n : B r i t i s h Columbia M a t e r i a l Examined: 60 Nymphs, B r i t i s h C o l u m b i a , N i c o l a Creek (G.G.E. S c u d d e r ) SUPERFAMILY CAENOIDEA FAMILY CAENIDAE SUBFAMILY CAENINAE A d u l t : S m a l l m a y f l i e s ; eyes of male s i m p l e , not grooved or d i v i d e d , f a r a p a r t ; l a t e r a l o c e l l i u s u a l l y l a r g e and p r o m i n e n t ; t a r s i 4-j o i n t e d , e x c e p t f o r an a d d i t i o n a l s h o r t b a s a l j o i n t on f o r e t a r s u s of the male; f o r e i u i n g w e l l d e v e l o p e d , e s p e c i a l l y i n the c u b i t o - a n a l r e g i o n ; wings o f t e n semi-opaque; u s u a l l y C and Sc t i n g e d w i t h p u r p l i s h e x c e p t a t the t i p ; o u t e r and p o s t e r i o r margins s e t a c e o u s ; Of of Rs v e r y deep; no m a r g i n a l i n t e r c a l a r i e s ; 2 l o n g c u b i t a l i n t e r -c a l a r i e s ; c r o s s v e i n s few; h i n d wing a b s e n t ; t a i l s t h r e e ; f o r c e p s base e n t i r e , e x c a v a t e d on a p i c a l m a r g i n , or w i t h a median and two l a t e r a l p r o j e c t i o n s on i t s a p i c a l m a r g i n . Nymph: Nymphs s p r a w l i n g , t a p e r e d p o s t e r i o r l y , d e n s e l y c o v e r e d w i t h f i n e h a i r s ; a l l c laws s i m i l a r ; l a t e r a l m argins of abdominal t e r g i t e s 2-9 produced i n t o f l a t e x t e n s i o n s b e a r i n g p o s t e r o - l a t e r a l s p i n e s ; g i l l s on segments 1-6; g i l l s on segment 1 r u d i m e n t a r y f i l a m e n t s ; g i l l s on segment 2 e l y t r o i d , a l m o s t c o m p l e t e l y c o v e r i n g a l l of the r e m a i n d e r ; t a i l s t h r e e , f r i n g e d e v e n l y on both s i d e s . GENUS CAENIS STEPHENS C a e n i s , Needham, 1935, The B i o l o g y of M a y f l i e s , -643 ( B i b l i o g r a p h y ) A d u l t : -Second j o i n t of antenna not more th a n t w i c e as l o n g as the b a s a l -200-j o i n t ; pronotum dee p l y e x c a v a t e d p o s t e r i o r l y i n the median a r e a ; p r e s t e r n u m two or t h r e e t i m e s l o n g e r than b r o a d , so t h a t the f o r e coxae are c l o s e t o g e t h e r ; f o r e l e g of male as l o n g as the body, c l a w s as i n T r i c o r y t h o d e s ; p o s t e r i o r branch of IT! and the l o n g i n t e r -c a l a r y between the branches of the ffl as l o n g as t h e a n t e r i o r b r a n c h , e x t e n d i n g to the base o f the wing; c r o s s v e i n s a r r a n g e d s i n g l y , . u s u a l l y no i n t e r c a l a r y space w i t h more than 1 c r o s s v e i n ; 2 or 3 c r o s s v e i n s o n l y i n r a d i a l r e g i o n ; t a i l s t h r e e , o f t e n 3 t i m e s t h e l e n g t h of the body i n the male, the m i d d l e t a i l may be s l i g h t l y l o n g e r ; abdomen u s u a l l y p a l e y e l l o w i s h w h i t e , t e r g i t e s o f t e n s u f f u s e d w i t h b l a c k i s h ; f o r c e p s base e n t i r e , a p i c a l margin s l i g h t l y convex; f o r c e p s 1 - j o i n t e d , s h a r p - p o i n t e d ; p o s t e r i o r margin of s u b a n a l p l a t e o f - f e m a l e e n t i r e ; penes u n i t e d , broad and p l a t e - l i k e . Nymph: Head and pronotum narrower t h a n the mesonotum, no t u b e r c l e s on the head; a p i c a l margin of labrum s l i g h t l y concave; m a n d i b u l a r c a n i n e s as i n - T r i c o r y t h o d e s ; m a x i l l a r y p a l p i 3 - j o i n t e d , t w i c e as l o n g as the g a l e a - l a c i n i a ; g l o s s a e and p a r a g l o s s a e not f u s e d as i n T r i c o r y t h o d e s ; l a b i a l p a l p i 3 - j o i n t e d ; c l a w s s l e n d e r , c u r v e d a p i c a l l y , not p e c t i n a t e ; g i l l s on abdominal segments 1-6; g i l l s on segment 1 w e l l d e v e l o p e d f i l a m e n t o u s r u d i m e n t s ; g i l l s on segment 2 o p e r c u l a t e , l a r g e , and q u a d r a t e , t h e i r o u t e r margins rounded; g i l l s on segments 3-6 f r i n g e d on o u t e r 2/3 of t h e i r e n t i r e m a r g i n s ; a l l g i l l s s i n g l e ; p o s t e r o - l a t e r a l s p i n e s on t e r g i t e s more prominent than i n T r i c o r y t h o d e s not u p c u r v e d ; t a i l s t h r e e , a w h o r l o f s p i n e s on each j o i n i n g . Genotype: C a e n i s macrura Stephens -201 CAENIS Key To Nymphs 1. Legs and t a i l s banded 2. Legs p a l e l y banded. T a i l s unbanded sp. 2 2. A n t e r i o r c o r n e r s of pronotum rounded sp. 1 A n t e r i o r c o r n e r s of pronotum sharp 3. 3. ITIesonotal wing pads w i t h dark l a t e r a l m a r g i n s , each b e a r i n g t h r e e dark l o b e s . No p a t t e r n on mesothorax sp. 3 ITiesonotal wing pads u n i c o l o u r e d . ITiesothorax w i t h a f a i n t V-shaped mark, open a n t e r i o r l y . . sp. 4 C a e n i s sp. 1 A d u l t : Unknown Nymph: A n t e r i o r c o r n e r s o f the pronotum rounded; p a l e s p o t s a t bases of wing pads; l e g s banded a l t e r n a t e l y l i g h t and dark; t a i l s a l t e r n a t e l y banded l i g h t and d a r k . D i s t r i b u t i o n : B r i t i s h Columbia M a t e r i a l Examined: The a u t h o r has examined many nymphs of t h i s s p e c i e s , t a k e n by Dr. G.G.E. Scudder from VI.17.61 t o V.26.63, from the f o l l o w i n g l o c a t i o n s : B r i t i s h C o l u m b i a : B o r t a n o Lake, Canim Lake, S p r i n g h o u s e Lake, White Lake, F e l f e e r L a k e , Green Lake, W i l l i a m s Lake. C a e n i s sp. 2 A d u l t : Unknown N.yrnph: A s m a l l e r p a l e nymph; a n t e r i o r p r o n o t a l c o r n e r s s h a r p ; pronotum w i t h 2 p a l e s p o t s ; mesonotum w i t h 2 m e d i a l and 2 l a t e r a l p a l e s p o t s , i n the form o f a diamond, or u n i c o l o u r o u s ; l e g s a l t e r n a t e l y banded -202-u j i t h p a l e and l i g h t brown; t a i l s unbanded. D i s t r i b u t i o n : B r i t i s h Columbia M a t e r i a l Examined: 11 Nymphs, B r i t i s h C o l u m b i a : B o i t a n o Lake, V.19.62 (G.G.E. S c u d d e r ) ; 13 Nymphs, B r i t i s h C o l u m b i a : S p r i n g h o u s e Lake, VI.2.62 (G.G.E. S c u d d e r ) ; 1 Nymph, B r i t i s h C o l u mbia: Rock Lake, IX.21.63 (G.G.E. S c u d d e r ) , 1 Nymph, B r i t i s h C o l u m b i a : W i l l i a m s Lake, VI,24.61 (G.G.E. S c u d d e r ) . C a e n i s s p. 3. A d u l t : Unknown Nymph: A n t e r i o r p r o n o t a l c o r n e r s s h a r p ; no p a t t e r n on mesonotum; mes o n o t a l wing pads w i t h dark l a t e r a l m a r g i n s , the i n n e r edges of t h e s e dark margins w i t h 3 p a l e i n d e n t a t i o n s each; l e g s a l t e r n a t e l y banded l i g h t and d a r k ; t a i l s a l t e r n a t e l y banded l i g h t and d a r k , the dark bands may be p a l e r . D i s t r i b u t i o n : B r i t i s h C o l umbia M a t e r i a l Examined: 4 Nymphs, B r i t i s h C o l u m b i a : S p r i n g h o u s e Lake, VI.18.61 (G.G.E. Scud d e r ) 3 Nymphs, B r i t i s h C o l u m b i a : B o i t a n o Lake, VI.17.61 (G.G.E. Scud d e r ) 2 Nymphs, B r i t i s h C o l u m b i a : F e l k e r Lake, VI.25.61 (G.G.E. Scudder) 1 Nymph, B r i t i s h C o l u m b i a : P a v i l i o n , VI.30.61 (G.G.E. Scudder) 21 Nymphs, B r i t i s h C o l u m b i a : Green Lake, VI.26.61 (G.G.E. Scudder) 1 Nymph, B r i t i s h C o l u m b i a : W i l l i a m s Lake, VI.24.61 (G.G.E. Scud d e r ) C a e n i s sp. 4 A d u l t : Unknown -203-Nymph: A n t e r i o r p r o n o t a l c o r n e r s s h a r p ; mesonotum w i t h a f a i n t U-shaped mark, the apex d i r e c t e d p o s t e r i o r l y ; no m a r k i n g s on the m e s o n o t a l wing pads; l e g s and t a i l s a l t e r n a t e l y banded l i g h t and d a r k . D i s t r i b u t i o n ; B r i t i s h Columbia M a t e r i a l Examined: 1 Nymph, B r i t i s h C o l u m b i a : Ulestujick, U.27.63 (G.G.E. Scud d e r ) 6 Nymphs, B r i t i s h C o l u m b i a : F e l k e r Lake, VI.25.61 (G.G.E. Scud d e r ) 5 Nymphs, B r i t i s h C o l u m b i a : Brunson Lake, VI.25.61 (G.G.E. Scudder) 1 Nymph, B r i t i s h C o l u m b i a : S p r i n g h o u s e Lake, VI;18.61 (G.G.E. Scudder) 2 Nymphs, B r i t i s h C o l u mbia: W i l l i a m s Lake, VI.24.61 (G.G.E. Scudder) SUPERFAMILY EPHEMEROIDEA FAMILY EPHEMERIDAE SUBFAMILY EPHEMERINAE A d u l t : U s u a l l y l a r g e m a y f l i e s ; eyes of male moderate to l a r g e , a p p r o x i -mated a p i c a l l y ; l e g s r a t h e r weak; t a r s i 4 - j o i n t e d , e x c e p t the f o r e t a r s u s of the male, which i s 5 - j o i n t e d ; c l a w s d i s s i m i l a r , e x c e p t the c l a w s on the male f o r e t a r s i ; which' are d i s s i m i l a r and b l u n t ; wings h y a l i n e ; v e i n s M and C u l s t r o n g l y d i v e r g e n t a t b a s e s ; M2 s t r o n g l y bent toward the Cu b a s a i l y ; s t i g m a t i c a r e a o f t e n narrowed; no sag i n the c o s t a l m a r g i n ; c r o s s v e i n s numerous; c o s t a l c r o s s v e i n s w e l l d e v e l o p e d ; m a r g i n a l i n t e r c a l a r i e s i r r e g u l a r ; c u b i t a l i n t e r c a l a r i e s resemble m a r g i n a l v e i n l e t s , c o n s i s t i n g of 2 to 4 f o r k s d e c u r v e n t from the a n t e r i o r branch of the c u b i t u s ; c o s t a l p r o j e c t i o n o f the h i n d wing low; Of of h i n d wing a b s e n t ; f o r c e p s 4 - j o i n t e d . Nymph: These a r e f o s s o r i a l , b u r r o w i n g nymphs; head w i t h a c o n s p i c u o u s -204-f r o n t a l p r o c e s s between the bases of the antennae; m a n d i b l e s w i t h e x t e r n a l t u s k s p r o j e c t i n g f o r w a r d and v i s i b l e d o r s a l l y ; t u s k s c u r v e upwards a p i c a l l y when viewed l a t e r a l l y , and d i v e r g e n t a t t i p s when viewed d o r s a l l y ; upper s u r f a c e s of t u s k s bear h a i r s o r s p i n e s , but not any t u b e r c l e s ; f o r e t i b i a e f o s s o r ' i a l ; g i l l s d o r s a l , c u r v i n g up over t h e abdomen, and w i t h f r i n g e d m a r g i n s . SUBFAMILY EPHEMERINAE Key To A d u l t s 1. C r o s s v e i n s somewhat crowded at and below b u l l a . Wings w i t h a v a r i a b l e p a t t e r n o f dark s p o t s Ephemera L i n n a e u s . C r o s s v e i n s not crowded a t b u l l a . Wings w i t h no d i s t i n c t p a t t e r n o f dark s p o t s , o f w i t h f o u r s m a l l d o t s a t or below b u l l a .2, 2. Penes t u b e - l i k e , t i p s n ot i n c u r v e d P e n t a q e n ja W a l s h Penes broader a t base t h a n a t apex, t i p s more or l e s s i n c u r v e d . . . Hexaqenia Walsh Key To Nymphs 1. F r o n t a l p r o c e s s o f head b i f i d Ephemera L i n n a e u s F r o n t a l p r o c e s s o f head e n t i r e and t r u n c a t e , c o n i c a l , o r rounded.. Hexaqenia Walsh GENUS EPHEMERA LINNAEUS Ephemera, Needham, 1935, The B i o l o g y o f M a y f l i e s , 246 ( B i b l i o g r a p h y ) A d u l t : Moderate s i z e d m a y f l i e s ; eyes of male s m a l l , s e p a r a t e d a p i c a l l y by a d i s t a n c e a t l e a s t as g r e a t as the d i a m e t e r o f the eyes; f o r e l e g of male alm o s t as l o n g as the body; femur l / 2 or l e s s t h e l e n g t h o f the t i b i a which i s e q u a l t o or s l i g h t l y l e s s than the l e n g t h o f the t a r s u s ; 2nd t a r s a l j o i n t the l o n g e s t ; i n h i n d l e g of b o t h sexes -205-fernur 3/4 the l e n g t h o f the t i b i a : f o r e w i n g s w i t h c r o s s v e i n s crowded a t and below the b u l l a ; dark band on f o r e w i n g from b u l l a to M; v a r i a b l e c l o u d s i n both w i n g s ; i n h i n d wing, IYI2 o f t e n detached from IY11 a t base, and d i r e c t e d toward the Cu; 2nd f o r c e p s j o i n t s t r o n g l y bowed, b e a r i n g a b a s a l e x t e n s i o n on the i n n e r margin:, penes i r r e g u l a r l y r o d - l i k e , s e p a r a t e d near base, a l m o s t p a r a l l e l , w i t h a l o n g s p i n e on the i n n e r margin o f each d i v i s i o n ; a p i c a l margin o f the s u b a n a l p l a t e of the female w i t h a U-shaped median c l e f t ; t a i l s t h r e e , e q u a l i n l e n g t h . Nymph: F r o n t a l p r o c e s s o f head b i f i d ; . m a n d i b u l a r t u s k s s l e n d e r , the margins smooth; m a x i l l a r y p a l p i 3 - j o i n t e d , s l e n d e r , l o n g , 2nd and 3 r d j o i n t s f r i n g e d w i t h l o n g h a i r s ; g a l e a - l a c i n i a s l e n d e r and p o i n t e d a p i c a l l y ; l a b i a l p a l p i 3 - j o i n t e d , the a p i c a l j o i n t widened a p i c a l l y w i t h the margin t r u n c a t e . Genotype: Ephemera v u l q a t a L. EPHEMERA SIIYIULANS WALKER Ephemera s i m u l a n s W a l k e r , Needham, 1935, The B i o l o g y of M a y f l i e s , 252 ( B i b l i o g r a p h y ) A d u l t : A dark brown m a y f l y ; head and thorax' deep b l a c k i s h brown; some p a l e m arkings on pronotum and mesonotum; l e g s r e d d i s h brown, j o i n i n g s d a r k e r ; f o r e w i n g t i n g e d w i t h brown, but not h e a v i l y b l o t c h e d or a p p e a r i n g b l a c k i s h ; s t r i p e a t b u l l a deep brown; i n a p i c a l t h i r d of wing are two dark brown c l o u d s , one a t the f o r k of the Rs and the o t h e r a t the f o r k i n the space below, n e a r e r the m a r g i n ; a c l o u d toward the margin from the i n n e r end of t h e b u l l a s t r i p e , and a n o t h e r a t the base of the l o n g i n t e r c a l a r y of the M; a l s o a s m a l l c l o u d between t h i s c l o u d and the b u l l a s t r i p e ; l o n g i t u d i n a l v e i n s dark brown; -206-c r o ' s s v e i n s b l a c k i s h , ; t h o s e i n the c o s t a l , s u b c o s t a l , and r a d i a l spaces w i d e l y margined e x c e p t a t the a p i c e s of the Sc and R; many c r o s s v e i n s i n t he d i s c and near the o u t e r margin w i d e l y margined; h i n d wing v e n a t i o n dark brown; v e i n s i n b a s a l s u b c o s t a l space and the d i s c d a r k - m a r g i n e d , f o r m i n g a number of s m a l l dark s p o t s i n the d i s c ; o u t e r margin w i d e l y t i n g e d w i t h l i g h t brown; abdominal t e r g i t e s p a l e brown, markings b l a c k i s h brown; a l a r g e i r r e g u l a r b l a c k i s on each l a t e r a l a r e a o f each t e r g i t e , based on the a n t e r i o r m a r g i n , the l a t e r a l and p o s t e r i o r edges d e e p l y e m a r g i n a t e , the l a t e r a l edges b l a c k ; the p o s t e r i o r margins o f the b a s a l and m i d d l e t e r g i t e s n a r r o w l y p a l e brown; p a l e brown median a r e a s w i d e s t on m i d d l e t e r g i t e s ; t e r g i t e s 7-9 each w i t h a p a i r of b l a c k submedian s t r e a k s , s h o r t on 7; s t e r n i t e s 1-6 each w i t h dark l a t e r a l t r i a n g l e s which a re w i d e s t p o s t e r i o r l y ; s t e r n i t e s 7-9 w i t h dark l a t e r a l l o n g i t u d i n a l s t r e a k s ; each s t e r n i t e w i t h a p a i r o f s m a l l dark submedian s p o t s and a p a i r o f s h o r t dark o b l i q u e submedian s t r e a k s from the a n t e r i o r m a r g i n ; m i d d l e of the s t e r n i t e 9 p a l e ; t a i l s deep y e l l o w to r e d d i s h brown, j o i n i n g s d a r k e r . Nymph; The f r o n t a l n o t c h r e g u l a r l y rounded; the m a n d i b u l a r t u s k s p r o j e c t beyond the f r o n t a l p r o c e s s a l m o s t t w i c e i t s l e n g t h , t h e o u t e r c u r v e s , i n d o r s a l v i e w , v i s i b l e o u t s i d e the antennae; g i l l s p u r p l i s h g r e y . D i s t r i b u t i o n : New York, M i c h i g a n , M i n n e s o t a , O n t a r i o , Montana, A l b e r t a , I l l i n o i s , Ohio, P e n n s y l v a n i a , Idaho, Wyoming, N o r t h C a r o l i n a , B r i t i s h C o l u mbia. -207-M a t e r i a l Examined; 17 Nymphs, B r i t i s h C o l u mbia: N i c o l a Creek (G.G.E. Scud d e r ) GENUS HEXAGENIA UJALSH He x a q e n i a , Needham,.1935, The B i o l o g y of M a y f l i e s , 258 ( B i b l i o g r a p h y ) A d u l t : Moderate s i z e d to l a r g e m a y f l i e s ; eyes of male moderate to l a r g e , a p p r o x i m a t e d a p i c a l l y or s e p a r a t e d by l e s s than the d i a m e t e r of one eye; i n both s e x e s , upper and l o w e r p o r t i o n s of the eye o f d i f f e r e n t c o l o u r s ; a n t e r i o r margin of pronotum ten d s to c o v e r the p o s t e r i o r margin of the head; f o r e l e g of male s h o r t e r than the body; f o r e femur of male s l i g h t l y l e s s than l / 2 the l e n g t h of the t i b i a , which i s 3/4 the l e n g t h of the t a r s u s ; 2nd t a r s a l j o i n t the l o n g e s t , a l m o s t l / 2 the l e n g t h of the t i b i a ; h i n d l e g of male w i t h femur s l i g h t l y s h o r t e r than the t i b i a ; i n f e m a l e , the j o i n t s a re s u b e q u a l ; c r o s s v e i n s of f o r e w i n g not crowded a t or b e f o r e t h e b u l l a ; c r o s s v e i n s i n d i s c o f one or both wings may be d a r k - m a r g i n e d ; no d i s t i n c t p a t t e r n of dark s p o t s on wings; penes u s u a l l y s e p a r a t e d near base, b r o a d e r a t base than a t apex, t i p s i n c u r v e d ; s u b a n a l p l a t e of female o n l y s l i g h t l y p r oduced a p i c a l l y ; t a i l s two. Nymphs: F r o n t a l p r o c e s s of head e n t i r e , i t s margin t r u n c a t e , c u r v e d , c o n i c a l , o r rounded; m a n d i b u l a r t u s k s l o n g , s l e n d e r , smooth, w i t h no r a s p - l i k e t e e t h , u p c u r v e d , t i p s d i v e r g e n t ; l a b i a l p a l p i 2 - j o i n t e d ; m a x i l l a r y p a l p i and g a l e a - l a c i n i a as i n Ephemera. Genotype: Hexaqenia b i l i n e a t a ( i n B a e t i s ) Say -208-HEXAGENIA LIMBATA (GUERIN) Hexaqenia l i m b a t a ( G u e r i n ) B u r k s , 1953, B u l l . Nat. H i s t . S u rv. 111. Hunt, 1953, B u l l . I n s t . F i s h . Res. No. 4, IKlich. Dept. o f C o n s e r v a t i o n ( b i b l i o g r a p h y . ) A d u l t : A p a l e y e l l o u j m a y f l y ; t h o r a x r e d d i s h brown; pronotum w i t h l a t e r a l b l a c k i s h s t r i p e s ; l e g s y e l l o w , f o r e femur and t i b i a b l a c k i s h ; wings h y a l i n e ; n ot t i n g e d w i t h p a l e b r o w n i s h g r e y ; c o s t a l m a r g i n of the f o r e w i n g a l m o s t as t r a n s p a r e n t as the a r e a behind i t ; no s p o t s on wing s ; o u t e r margin o f h i n d wing brown; abdominal t e r g i t e s y e l l o w w i t h a wide da r k , brown m i d - d o r s a l l i n e ; each t e r g i t e w i t h brown l a t e r a l s t r i p e s b e g i n n i n g a t the a n t e r i o r c o r n e r s and e x t e n d i n g back t o meet the median s t r i p e a t the p o s t e r i o r m a r g i n ; penes hook-l i k e ; t a i l segments p a l e y e l l o w i s h b a s a l l y , dark brown d i s t a l l y . Nymph: F r o n t a l p r o c e s s o f head dome shaped; each p o r t i o n o f 1 s t p a i r o f g i l l s composed of 2 or more f i l a m e n t s . D i s t r i b u t i o n : B r i t i s h C o l umbia No specimens of t h i s s p e c i e s were examined. GENUS PENTAGENIA UJALSH P e n t a q e n i a , Needham, 1935, The B i o l o g y o f M a y f l i e s , 255 ( B i b l i o g r a p h y ) A d u l t : Large m a y f l i e s ; eyes o f male l a r g e , a p p r o x i m a t e d a p i c a l l y ; f o r e l e g o f male o n l y s l i g h t l y l o n g e r than the head and t h o r a x combined; f o r e femur 2/3 t o 3/4 the l e n g t h of the t i b i a ; t a r s u s s l i g h t l y l o n g e r -209-than the t i b i a ; h i n d l e g v e r y s i m i l a r to f o r e l e g ; wing v e n a t i o n much as i n Hexaqenia; c e l l s i n the c o s t a l p r o j e c t i o n o f the h i n d wing may be d i v i d e d by a c r o s s l i n e i n t o two s e r i e s ; penes s i m p l e , r e d - l i k e , u n i t e d o n l y a t base, d i v e r g e n t a p i c a l l y ; s u b a n a i p l a t e of female w i t h a U-shaped median notch on the a p i c a l m a r g i n , and a s h o r t p r o j e c t i o n d i r e c t e d outward and backward a t each o u t e r c o r n e r ; t a i l s t h r e e , m i d d l e one very s h o r t . Nymph: F r o n t a l p r o c e s s o f head b i f i d ; m a n d i b u l a r t u s k s s t o u t , c r e v a t e on upper m a r g i n ; m a x i l l a r y p a l p i 3 - j o i n t e d , s t o u t , the 2nd and 3 r d j o i n t s f r i n g e d w i t h l o n g h a i r s ; g a l e a - l a c i n i a wide and c o n i c a l ; l a b i a l p a l p i 2 - j o i n t e d , the d i s t a l j o i n t l o n g , c l a v a t e , c o v e r e d d e n s e l y w i t h l o n g h a i r s and s e v e r a l l o n g s p i n e s near the t i p s . Genotype: P e n t a q e n i a v i t t i q e r a ( i n P a l i n q e n i a ) UJalsh P e n t a q e n i a sp. 1 A d u l t : A v e r y l a r g e y e l l o w i s h brown m a y f l y ; eyes r e d d i s h i n the d o r s a l l / 4 , b l a c k i n the v e n t r a l 3/4; f o r e l e g s dark brown; wings h y a l i n e ; no s p o t s on win g s ; v e n a t i o n dark brown; p o s t e r i o r margins o f h i n d wings dark; abdominal t e r g i t e s y e l l o w w i t h a dark median s t r i p e ; each t e r g i t e w i t h an o b l i q u e brown s t r i p e from the a n t e r o - l a t e r a l c o r n e r s to the p o s t e r i o r b o r d e r ; each s t e r n i t e w i t h a brown median s t r i p e , w i d e n i n g a n t e r i o r l y ; t a i l s , f o r c e p s dark brown. Nymph: Unknown D i s t r i b u t i o n : B r i t i s h Columbia M a t e r i a l Examined: 1 Male, B r i t i s h C o l u m b i a , Summerland, VI.20.58 \u00C2\u00A3K. T a y l o r ) , -210-1 male, B r i t i s h C o l u m b i a : Vernon, IX.6.48 (D. E v a n s ) , 1 Male, B r i t i s h C o l u m b i a : Summerland, V I I I . ? . 5 7 , 1 M a l e , B r i t i s h C o l u m b i a : Okanagan Lake, V I I I . 8 . 3 5 ( 3 . L . McHugh) -211 '' \u00C2\u00A3JL '^\u00C2\u00A3M^^J.JQ.J^_AJi2.^-\u00C2\u00A3S.Ji\u00C2\u00A3.'k'LLS_io.w.s, T h i s t h e s i s encompasses a taxonomic i n v e s t i g a t i o n of the Ephemeroptera of B r i t i s h C o l u m b i a , a group o f i n s e c t s u/hich has been c o m p l e t e l y n e g l e c t e d i n t h i s p r o v i n c e . The c o n s i d e r a b l e s t r u c t u r a l v a r i a t i o n among the h i g h e r r a n k s of the Ephemeroptera and t h e c o n s t a n c y of taxonomic c r i t e r i a w i t h i n each s p e c i e s p r o v i d e t h e t a x o n o m i s t w i t h a r e w a r d i n g o r d e r f o r s t u d y . In t he ' a d u l t s , p a r t i c u l a r l y u s e f u l c r i t e r i a i n c l u d e the d i s t i n c t and e a s i l y i d e n t i f i a b l e wing v e n a t i o n , the s t r u c t u r e o f the compound e y e s , t h e morphology o f t h e l e g s , the shape o f the male g e n i t a l i a , and the c o l o u r p a t t e r n of t h e body. I d e n t i f i c a t i o n i s f a c i l i t a t e d i f specimens of both s e x e s a re a v a i l a b l e f o r s t u d y , . as a l l o f t h e s e c h a r a c t e r i s t i c s e x h i b i t some s e x u a l dimorphism i n a number of s p e c i e s . The p o s i t i o n of the o c e l l i , t he wing c o l o u r , the l e n g t h o f the t a i l s , t he form o f the antennae, and the g e n e r a l c o l o u r o f the i n s e c t a r e l e s s v a l u a b l e taxonomic f e a t u r e s . The p r i m a r y taxonomic c h a r a c t e r i s t i c s o f t h e nymphs are the shape o f the,body, the m o d i f i c a t i o n s o f the m o u t h p a r t s , and the type o f g i l l s . The d e n t i c u l a t i o n and shape of the c l a w s , t h e number, c o l o u r p a t t e r n , and v e s t i t u r e of the t a i l s , and the c o l o u r p a t t e r n of the t e r g i t e s a r e a l s o e s p e c i a l l y u s e f u l f o r i d e n t i f i c a t i o n . The s t r u c t u r e o f the compound e y e s , o c e l l i , antennae, and l e g s are of l i m i t e d v a l u e . I n c l u d e d i n t h i s paper i s a c h e c k l i s t o f a l l s p e c i e s r e p o r t e d o r c o l l e c t e d i n B r i t i s h C o l u m b i a , c o n s i s t i n g o f 146 s p e c i e s i n 23 g e n e r a ; keys to a d u l t s and nymphs; d e s c r i p t i o n s o f t a x o n o m i c a l l y -212-p e r t i n e n t c r i t e r i a o f the a d u l t s and nymphs', and some a c c o u n t o f the e c o l o g y of tho s e specimens c o l l e c t e d by the a u t h o r on the A l o u e t t e R i v e r . A l t h o u g h the e c o l o g y of the m a y f l i e s has not been e x t e n s i v e l y i n v e s t i g a t e d d u r i n g t h i s s t u d y , c e r t a i n f a c t s and t r e n d s have been o b s e r v e d . No p r e f e r e n c e on the p a r t o f the nymphs f o r e i t h e r the m i d d l e or edges of the r i v e r was d e t e r m i n e d . However, s i n c e t h e A l o u e t t e R i v e r i s g e n e r a l l y narrow, between twenty and f o r t y f e e t i n w i d t h , t h e r e i s i n most p l a c e s l i t t l e v a r i a t i o n i n c u r r e n t o r c o m p o s i t i o n o f t h e stre a m bed between the m i d d l e and the edges. At the w i d e s t p a r t of t h e r i v e r , near the mouth, s a m p l i n g was s u c c e s s f u l o n l y a t the edges, so t h a t no co m p a r i s o n w i t h the m i d d l e was p o s s i b l e . Because of the s a m p l i n g methods, a c l e a r i n d i c a t i o n of the p r e f e r e n c e o f v a r i o u s nymphs f o r p a r t i c l e s i z e o f the m a t e r i a l o f the s t r e a m bed was not o b t a i n a b l e . In most l o c a t i o n s mud, sand, f i n e and c o a r s e g r a v e l , and r o c k s of a l l s i z e s were p r e s e n t , and at many s a m p l i n g s t a t i o n s t h e r e were a l s o b o u l d e r s and b e d r o c k . The use of the d i p net p r e c l u d e d the p o s s i b i l i t y of o b s e r v i n g the e x a c t e c o l o g i c a l n i c h e o f the nymphs c o l l e c t e d . lYIost s p e c i e s t a k e n i n the A l o u e t t e R i v e r were found i n l o c a t i o n s c o n t a i n i n g a l l t y p e s of stream bed from mud to bedr o c k . However, Epeorus s p. 2, Epeorus sp.4, E p h e m e r e l l a t e r e s a and E p h e m e r e l l a d o d d s i were never found i n mud or sand. C a e n i s s p . 1. S i p h l o n u r u s sp. 1, C a l l i b a e t i s s p . 1, and C e n t r o p t i l u m s p . 2 were found p r e d o m i n a n t l y i n mud and s i l t , i n l o c a t i o n s where t h e r e was o c c a s i o n a l sand, g r a v e l , o r r o c k s . -213-H e p t a g e n i a sp. 3 was never found i n sand. E p h e m e r e l l a l o d i was u s u a l l y t a k e n i n q u i e t water from mud and s i l t , a l t h o u g h i n one case some nymphs were c o l l e c t e d from a r i p p l y s t r e a m , amongst g r a v e l , r o c k s and b o u l d e r s . Four s p e c i e s : f-'N.eocloeon sp. 1, E p h e m e r e l l a i n e r m i s , P a r a l e p t o p h l e b i a sp. 1 and P a r a l e p t o p h l e b i a s p . 2 were t a k e n , among o t h e r p l a c e s , from a q u i e t , c l a y - b o t t o m e d p o o l . IKlost o f the s p e c i e s o f nymphs t a k e n i n the A l o u e t t e R i v e r were found i n a l l c u r r e n t s , from q u i e t water t o t u r b u l e n t r a p i d s . Four s p e c i e s , however: E p h e m e r e l l a t e r e s a , E p h e m e r e l l a d o d d s i , Epeorus s p. 2, and Epeorus sp..4, were found o n l y i n a r a p i d , t u r b u l e n t c u r r e n t . Three s p e c i e s : C a e n i s s p. 1, S i p h o n u r u s sp. 1 and C e n t r o p t i l u r a sp. 2 were taken o n l y i n q u i e t , slow w a t e r . On the o t h e r hand, i.Nsocloeon sp. 1, E p h e m e r e l l a l o d i , C a l l i b a e t i s s p . 1, P a r a l e p t o p h l e b i a b i c o r n u t a , H e p t a q e n i a s p. 3 and B a e t i s s p . 1 were never found i n r a p i d water, and E p h e m e r e l l a s p i n i f e r a , Epeorus s p . 3 and B a e t i s s p . 1 were never t a k e n i n q u i e t or slow w a t e r . Burks (1953) s t a t e s t h a t Hexaqenia l i m b a t a p r e f e r s l a r g e s l ow r i v e r s and m o d e r a t e l y s i z e d f a i r l y r a p i d r i v e r s ; Stenonema sp. and H e p t a q e n i a s p . p r e f e r m o d e r a t e l y s i z e d , f a i r l y r a p i d r i v e r s and s m a l l r a p i d r i v e r s or c r e e k s ; Ephemera s i m u l a n s p r e f e r s s m a l l r a p i d r i v e r s o r c r e e k s and l a r g e l a k e s ; and L e p t o p h l e b i a n e b u l o s a , L. c u p i d a and T r i c o r y t h o d e s sp. p r e f e r temporary ponds, u s u a l l y a l o n g the .margins o f s t r e a m s , w i t h a reduced c u r r e n t o r none. Some s p e c i e s o f nymphs were t a k e n d u r i n g the e n t i r e y e a r , w h i l e o t h e r s were taken o n l y d u r i n g p e r i o d s r a n g i n g from one to -214-seven months. T h i s i s p r o b a b l y not s i g n i f i c a n t , as t h i s s i t u a t i o n c o u l d too e a s i l y be due to chance. There i s a p o s s i b i l i t y t h a t some s p e c i e s become more a c t i v e d u r i n g c e r t a i n t i m e s of the y e a r , but as t h o s e s p e c i e s ( e x c e p t f o r E p h e m e r e l l a f l a v i l i n e a ) c o l l e c t e d d u r i n g a l i m i t e d p a r t of t h e year mere t a k e n d u r i n g t h e summer months, i t was q u i t e p r o b a b l y due to the i n c r e a s e d a c t i v i t y of t h e c o l l e c t o r . Almost a l l o f the specimens were taken a t depths o f one to t h r e e f e e t . T h i s , however, i s a g a i n not s i g n i f i c a n t , as the use of a S u r b e r Sampler or d i p n e t i s not f e a s i b l e a t depths much g r e a t e r than t h i s . Dr. G.G.E. Scudder has c o l l e c t e d e x t e n s i v e l y i n the l a k e s o f the C h i l c o t i n , C a r i b o o and N i c o l a V a l l e y r e g i o n s . He d e t e r m i n e d the pH and t h e s a l i n i t y o f each l o c a t i o n from which he sampled. A l l the l a k e s were n e u t r a l o r a l k a l i n e , r a n g i n g from a pH of 6.84 t o 10.55, the m a j o r i t y r a n g i n g up from pH 7.53. No c o r r e l a t i o n was found i n the p r e s e n t s t u d y between the s p e c i e s c o l l e c t e d and the pH o f the en v i r o n m e n t , o r between the s p e c i e s c o l l e c t e d and the s a l i n i t y o f the l a k e . The amount o f m a t e r i a l a v a i l a b l e f o r stu d y was l i m i t e d , and t h e r e f o r e t h i s paper does not p r o v i d e a complete a c c o u n t of the Ephemeroptera o f B r i t i s h C olumbia. R a t h e r , i t i s i n t e n d e d as a b a s i s f o r f u r t h e r work. F i r s t l y , more complete s e a r c h of the l i t e r a t u r e and e x a m i n a t i o n o f type m a t e r i a l may p r o v i d e i d e n t i t i e s t o some o f the 62 unknown s p e c i e s r e c o r d e d h e r e i n . The r e a r i n g of u n i d e n t i f i e d nymphs t o a d u l t s may det e r m i n e the i d e n t i t y o f o t h e r s . T h i s may be a c h i e v e d by submerging cages o f t h e nymphs i n s t r e a m s , o r w i t h more d i f f i c u l t y , r e a r i n g them i n a r t i f i c i a l -215-s t r e s m s i n the l a b o r a t o r y . Those specimens r e m a i n i n g u n i d e n t i f i e d s h o u l d then be more c o m p l e t e l y d e s c r i b e d and named. S e c o n d l y , a g r e a t d e a l of a d d i t i o n a l c o l l e c t i n g i s n e c e s s a r y t o complete our knowledge of t h i s group i n t h i s p r o v i n c e . L i t t l e i s known, as y e t , of the b i o l o g y and e c o l o g y of many s p e c i e s . F u r t h e r work i n t h e s e f i e l d s would be i l l u m i n a t i n g . The \" p r e f e r e n c e \" o f t h e v a r i o u s s p e c i e s f o r l a k e s and r i v e r s , r a t e o f c u r r e n t , degree of t e m p e r a t u r e , s a l i n i t y and pH of the environment i s l a r g e l y unknown. C.H. E r i k s e n (1963a, 1963b) has c o n t i n u e d the r e s e a r c h of 3.P. L i n d u s k a (1942) on the p r e f e r e n c e of some nymphs f o r p a r t i c l e s i z e of the s u b s t r a t e . C o l l e c t i n g t e c h n i q u e s make i t d i f f i c u l t t o s t u d y t h i s a s p e c t i n t h e f i e l d , and t h e r e f o r e h i s e x p e r i m e n t a l approach i s of g r e a t v a l u e . A c o n t i n u a t i o n and e x p a n s i o n of t h i s t o o t h e r s p e c i e s would be b e n e f i c i a l . The d i v e r s i t y among body forms of the nymphs would make a study of t h e r e l a t i o n s h i p between body form and environment of v a l u e . Research a l o n g t h i s l i n e has a l r e a d y been i n t r o d u c e d by G.S. Dodds and F.L. H i s a ^ (1924a, 1924b). The minute d i f f e r e n c e s between some s p e c i e s ( ? ) a f f o r d s an o p p o r t u n i t y t o s t u d y the p o s s i b i l i t y o f g e o g r a p h i c v a r i a t i o n w i t h i n t h i s o r d e r of i n s e c t s . -216-S U ffl IYJ A R Y T h i s paper was u n d e r t a k e n to amalgamate the e x i s t i n g knowledge of the Ephemeroptera of B r i t i s h Columbia and t o c o n t r i b u t e to i t , to c l a r i f y the taxonomy c o n s i s t e n t w i t h the newer i d e a s o f c l a s s i f i c a t i o n o f t h i s group, and t o p r o v i d e a b a s i s f o r f u r t h e r i n v e s t i g a t i o n . Whereas the taxonomy of the o r d e r has been w e l l s t u d i e d i n the U n i t e d S t a t e s , i t has been l a r g e l y n e g l e c t e d i n Canada, and p a r t i c u l a r l y i n B r i t i s h C o l u m b i a . The Ephemeroptera p r o v i d e a s a t i s f y i n g group w i t h which t o work as they e x h i b i t d i s t i n c t and c o n s i s t e n t taxonomic c r i t e r i a , a l t h o u g h a c o n s i d e r a b l e degree of s e x u a l dimorphism makes the c o n s t r u c t i o n of keys d i f f i c u l t . The system of c l a s s i f i c a t i o n p roposed by Edmunds and T r a v e r (1954) i n which the t h r e e f a m i l i e s H e p t a g e n i i d a e , Ephemeridae, and B a e t i d a e a r e r e p l a c e d by the f i v e s u p e r f a m i l i e s Heptagen-o i d e a , L e p t o p h l e b i o i d e a , C a e n o i d e a , Ephemeroidea, and P r o s o -p i s t o m a t o i d e a , i s employed. A l l but the l a s t a r e r e p r e s e n t e d i n t h i s p r o v i n c e . 146 s p e c i e s i n 23 genera have been r e c o r d e d from B r i t i s h C o lumbia. Df t h e s e , 62 s p e c i e s are as y e t . n o t i d e n t i f i e d by t h e a u t h o r and have been d e s i g n a t e d by number. A c h e c k l i s t , k e y s , and d e s c r i p t i o n s o f t a x o n o m i c a l l y p e r t i n e n t c r i t e r i a o f a l l r e c o r d e d s p e c i e s and h i g h e r r a n k s are i n c l u d e d h e r e i n . A c u r s o r y i n v e s t i g a t i o n of the e c o l o g y of the nymphs i n v o l v e d r e g u l a r c o l l e c t i o n s from 20 l o c a t i o n s , chosen to p r o v i d e a l l -217-t y p e s o f s u b s t r a t e and r a t e s of c u r r e n t f l o w , on the A l o u e t t e R i v e r , near Haney. No \" p r e f e r e n c e \" f o r the m i d d l e or edges of the r i v e r was e x h i b i t e d by the nymphs. Most s p e c i e s were taken from a l l t y p e s o f stream bed. T h i s , however, i s not s i g n i f i c a n t , as the use of a d i p net does not l e n d i t s e l f t o an a c c u r a t e d e t e r m i n a t i o n of p a r t i c l e s i z e \" p r e f e r e n c e \" . The e x p e r i m e n t a l approach t o t h i s problem o f C.H. E r i k s e n (1963) i s of more v a l u e than f i e l d o b s e r v a t i o n s . There i s no c o r r e l a t i o n between the s p e c i e s of nymphs and the pH or the s a l i n i t y o f the e n v i r o n m e n t . In o r d e r to e x t e n d our knowledge of the Ephemeroptera of B r i t i s h C o l u m b i a , i t would be d e s i r a b l e t o c o l l e c t i n h i t h e r t o untouched r e g i o n s o f the p r o v i n c e , and t o f u r t h e r i n v e s t i g a t e the i d e n t i t i e s of the 62 u n i d e n t i f i e d s p e c i e s by f u r t h e r r e s e a r c h i n t o the l i t e r a t u r e , e x a m i n a t i o n o f type m a t e r i a l , and r e a r i n g of nymphs. New s p e c i e s s h o u l d then be d e s c r i b e d and named. F u r t h e r s t u d y of the e c o l o g y and b i o l o g y of members of t h i s o r d e r would be r e w a r d i n g . -218-L I ILIL h. I LL \u00C2\u00A3 I \u00C2\u00A3 1 1 1 2 A l l e n , R.K., and G.F. Edmunds, Or., 1957. A R e v i s i o n o f The Genus E p h e m e r e l l a (Ephemeroptera: E p h e m e r e l l i d a e ) I . The Subgenus Timpanoqa. Can. E n t . -.91:51-58. 1961. A R e v i s i o n o f t h e Genus E p h e m e r e l l a (Ephemeroptera: E p h e m e r e l l i d a e ) I I . The Subgenus C a u d a t e l l a . Ann. E n t . S o c Amer. 54:603-612, 1961. A R e v i s i o n o f the Genus E p h e m e r e l l a (Ephemeroptera: E p h e m e r e l l i d a e ) I I I . The Subgenus A t t e n u a t e l l a . Dourn. Kansas Ent. Soc. 34:161-173. 1962. A R e v i s i o n o f the Genus E p h e m e r e l l a (Ephemeroptera: E p h e m e r e l l i d a e ) IV. The Subgenus D a n n e l l a . Oourn. Kansas Ent . Soc. 35:333-338. 1962. A R e v i s i o n o f the Genus E p h e m e r e l l a (Ephemeroptera: E p h e m e r e l l i d a e ) V. The Subgenus D r u n s l l a . IMsc. Pub. E n t . Soc. Amer. .3(5) :145-180. 1963. A R e v i s i o n , o f the Genus E p h e m e r e l l a (Ephemeroptera: E p h e m e r e l l i d a e ) V I . The Subgenus S e f r a t e l l a . Ann. E n t . Soc. Amer. 56(5):583-600. . 1963. H R e v i s i o n o f the Genus E p h e m e r e l l a (Ephemeroptera: E p h e m e r e l l i d a e ) V I I . The Subgenus E u r y l o p h e l l a . Can. E n t . 95 ( 6 ) : 597-623. B e r n e r , L., 1940, B a e t i n e m a y f l i e s from F l o r i d a ( E p h e m e r o p t e r a ) . F l o r i d a E n t . 23:33-45; 49-62. 1950. The m a y f l i e s of F l o r i d a . U n i v . F l o r i d a S t u d i e s , B i o l . S c i . S e r i e s 4 ( 4 ) , 1953. New m a y f l y r e c o r d s from F l o r i d a and a d e s c r i p t i o n o f a new s p e c i e s . F l o r i d a E n t . 36:145-9. 1955. A new s p e c i e s of P a r a l e p t o p h l e b i a from the S o u t h e a s t (Ephemeroptera: L e p t o p h l e b i i d a e ) . P r o c . E n t . Soc. Wash. 57:245-7. 1956. The Genus Neoephemera i n N o r t h America (Ephemeroptera: Neoephemeridae). Ann. Ent. Soc. Amer. 49:33-42. B u r k s , B.D., 1946. New Heptagenine m a y f l i e s . ' Ann. E n t . Soc. Amer. 39:607-615. 1949. New s p e c i e s of E p h e m e r e l l a from I l l i n o i s ( E p h e m e r o p t e r a ) . Can. E n t . 79:232-6. 1953. The m a y f l i e s , or Ephemeroptera, of I l l i n o i s . B u l l . 111. Nat. H i s t . S u r v . 26:1-216. -219-Day, UJ.C, 1952. New s p e c i e s and n o t e s on C a l i f o r n i a m a y f l i e s ( E p h e m e r o p t e r a ) , Pan-Pac. En t . 28:17-39. 1953. A new m a y f l y genus from C a l i f o r n i a ( E p h e m e r o p t e r a ) . Pan-Pac. Ent. 29:19-24. 1954. New s p e c i e s and n o t e s on C a l i f o r n i a m a y f l i e s , I I . Pan-Pac. Ent. 30:29-34. 1955. New genera of m a y f l i e s from C a l i f o r n i a ( E p h e m e r o p t e r a ) . \u00E2\u0080\u00A2 Pan-Pac. E n t . 31:121-37. Dodds, G.S. and F.L. Hisaw, 1924. E c o l o g i c a l s t u d i e s of a q u a t i c i n s e c t s : I . S i z e of r e s p i r a t o r y organs i n r e l a t i o n t o e n v i r o n m e n t a l c o n d i t i o n s . E c o l o g y , 4: 262-271. 1924. E c o l o g i c a l s t u d i e s of a c q u a t i c i n s e c t s . I I . A d a p t a t i o n s of m a y f l y nymphs to s w i f t s t r e a m s . E c o l o g y , 5: 137-148. E a t o n , A.E., 1883-88. A r e v i s i d n a l monograph of r e c e n t Ephemeridae o r m a y f l i e s . T r a n s . L i n n . Soc. London, Sec. S e r . Z o o l . 3: 1-352. 1901. Ephemeridae c o l l e c t e d by H e r r . E. S t r a n d i n South and A r c t i c Norway. E n t . Month, mag. 37:252-5. Edmunds, G.F. J r . , 1959. S u b g e n e r i c groups w i t h i n the m a y f l y genus E p h e m e r e l l a (Ephemeroptera: E p h e m e r e l l i d a e ) . Ann. E n t . Soc. Amer. 52:543-547. 1962. T h e . p r i n c i p l e s a p p l i e d i n d e t e r m i n i n g the h i e r a r c h i c l e v e l o f the h i g h e r c a t e g o r i e s of Ephemeroptera. S y s t e m a t i c Z o o l o g y , 11:22-31. Edmunds, G.F. Or. and R.K.. A l l e n , 1957. A c h e c k l i s t of t h e Ephemer-o p t e r a of N o r t h America n o r t h of M e x i c o . Ann. Ent. Soc. Amer. 50: 317-324. Edmunds, G.F. Dr. and 3.R. T r a v e r , 1954. An o u t l i n e c f a r e c l a s s i -f i c a t i o n o f the Ephemeroptera. P r o c . E n t . Soc. Ulash. 56: 236-240. E r i c s e n , , ( X . , 1963, The R e l a t i o n o f Oxygen Consumption to S u b s t r a t e P a r t i c l e S i z e i n Two B u r r o w i n g M a y f l i e s . 0. Exp. B i o l . 40: 447-453. Eri k s ' e n , C.H., 1963. R e s p i r a t i o n R e g u l a t i o n i n Ephemera s i r n u l a n s UJalker and Hexaqenia l i m b a t a ( S e r v i l l e ) ( E p h e m e r o p t e r a ) . 0. Exp. B i o l . 40:455-467. Id e , F.P. 1930. C o n t r i b u t i o n to the b i o l o g y of O n t a r i o m a y f l i e s w i t h d e s c r i p t i o n s of new s p e c i e s . Can. E n t . 62: 204-13, 218-31. . -220-1937. D e s c r i p t i o n s o f e a s t e r n N o r t h American s p e c i e s o f B a e t i n e m a y f l i e s w i t h p a r t i c u l a r r e f e r e n c e to the nymphol s t a g e s . Can. E n t . 69:219-31, 235-43. 1954. The nymph of R i t h r o q e n a i m p e r s o n a t a (Ephemerida) and a new c l o s e l y r e l a t e d s p e c i e s from the same l o c a l i t y i n S o u t h e r n O n t a r i o . Can. Ent. 86:348-56. L i n d u s k a , J.P., 1942. Bottom t y p e s as a f a c t o r i n f l u e n c i n g the l o c a l d i s t r i b u t i o n of m a y f l y nymphs. Can. Ent. 74:26-30. Mayo, U.K., 1939. New 'western Ephemeroptera. Pan-Pac. E n t . 15: 145-154. 1951. New 'western Ephemeroptera I I . Pan-Pac. Ent. 27:121-125. 1952. New w e s t e r n Ephemeroptera I I I . Pan-Pac. Ent. 28:93-103. 1952. New Western \u00E2\u0080\u00A2\u00E2\u0080\u00A2.Ephemeroptera IU. Pan-Pac. Ent. 28:179-186. (YlcDunnough, 3., 1921. Two new Canadian m a y f l i e s ( E p h e m e r i d a e ) . Can. E n t . 53: 117-120. 1936. A new a r c t i c B a e t i d ( E p h e m e r o p t e r a ) . Can. Ent. 68: 33-35. 1936. F u r t h e r n o t e s on the genus Ameletus w i t h d e s c r i p t i o n s of new s p e c i e s . ( E p h e m e r o p t e r a ) . Can. Ent. 68:207-11. 1938. New s p e c i e s of N o r t h American Ephemeroptera w i t h c r i t i c a l n o t e s . Can. Ent. 70:23-34. 1939. New B r i t i s h Columbian Ephemeroptera. Can. Ent. 71:49-54. 1942. An a p p a r e n t l y new T h r a u l o d e s from A r i z o n a ( E p h e m e r i d a ) . Can. Ent. 74:117. 1943. A new Cinyqmula from B r i t i s h Columbia ( E p h e m e r o p t e r a ) . Can. Ent. 75:3 Needham, 0 C , 3.R. T r a v e r , and Y i n - C h i Hsu., 1935. The B i o l o g y of M a y f l i e s w i t h a S y s t e m a t i c Account o f N o r t h American S p e c i e s . Comstock, I t h a c a , N.Y. S p i e t h , H.T., 1933. The Phylogeny o f Some M a y f l y Genera. 3. N.Y. E n t . Soc. 41:55-86, 327-391. 1938. A method of r e a r i n g Hexagenia nymphs. Ent. News. 49:29-32. 1938. Two i n t e r e s t i n g m a y f l y nymphs w i t h a d e s c r i p t i o n o f a new s p e c i e s . Amer. Mus. N o v i a t e s 970:1-7. -221-1938. Taxonomic s t u d i e s on the Ephemerida. I : D e s c r i p t i o n s o f New North American s p e c i e s . Amer. fflus. N o v i a t e s . 1002: 1-11. 1940. The N o r t h American Ephemeropterans s p e c i e s o f F r a n c i s l U a l k e r . Ann. Ent. Soc. Amer. 33:324-38. 1941.. The N o r t h American Ephemeropteran s p e c i e s of the Rev. A.E. E a t o n . Ann. E n t . Soc. Amer. 34:87-98. 1941. Taxonomic s t u d i e s on the Ephemeroptera I I . The genus Hexaqenia . Amer. M i d . Nat. 24 (2):233-280. 1947. Taxonomic s t u d i e s on the Ephemeroptera IV. The genus Stenonema. Ann. Ent. Soc. Amer. 40 ( l ) : 8 7 - 1 2 2 . S p r u l e s , ID. IYI., 1947. An e c o l o g i c a l i n v e s t i g a t i o n o f stream i n s e c t s i n A l g o n q u i n P a r k , O n t a r i o . U n i v . Toronto S t u d i e s , B i o l . S e r . 56, Pub. Ont. E i s h . Res. Lab. 69:1-81. U p h o l t , 111.IYI. 1936. A new s p e c i e s o f m a y f l y from C a l i f o r n i a (Epheme B a e t i d a e ) . Pan-Pac. E n t . 12:120-2. 1937. Two new m a y f l i e s from the P a c i f i c C o a s t . Pan-Pac. Ent. 13:85-88, -222-PLATE I A diagram of t h e main t o p o g r a p h i c f e a t u r e s of a m a y f l y wing (based on a f o r e wing o f I r o n o p s i s permaqnus), c r o s s v e i n s of the m i d d l e f i e l d m o s t l y o m i t t e d . The numerals 1, 2, and 3 d e s i g n a t e s u c c -e s s i v e f o r k s i n the t r i p l e t r i a d o f the r a d i a l s e c t o r ; f o r k s 2 and 3 are not p r e s e n t i n the h i n d wing of r e c e n t m a y f l i e s . Of, o u t e r f o r k of Rs. ( a f t e r Needham, T r a v e r , and Hsu, 1935). R e p r e s e n t a t i v e mouthparts of t h e m a y f l y nymph. A, r i g h t m a n d ible o f B l a s t u r u s ; - s p . ; B, m a x i l l a of L e p t o p h l e b i a s p . ; C, l a b i u m of S i p h l o n u r u s sp. ( a f t e r S p i e t h , 1933). PL RTE' I -223-PLATE I I Wale g e n i t a l i a of some Heptagenine and B a e t i d m a y f l i e s , ( n o t drawn to s c a l e ) , ( a f t e r Needham, T r a v e r , and Hsu, 1935). P L A T F I I . \u00C2\u00A3 f> e o r v s J f e. n 9 n e m "Thesis/Dissertation"@en . "10.14288/1.0093730"@en . "eng"@en . "Zoology"@en . "Vancouver : University of British Columbia Library"@en . "University of British Columbia"@en . "For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use."@en . "Graduate"@en . "A contribution to the ephemeroptera of British Columbia"@en . "Text"@en . "http://hdl.handle.net/2429/37620"@en .